Chapter X: Appendix: Note a

STEAM FRIGATE.

_Report of HENRY RUTGERS, SAMUEL L. MITCHEL, and THOMAS MORRIS, the Commissioners superintending the construction of a steam vessel of war, to the Secretary of the Navy._

NEW YORK, _December 28th, 1815_.

SIR:

The war which was terminated by the treaty of Ghent, afforded, during its short continuance, a glorious display of the valor of the United States by land and by sea--it made them much better known to foreign nations, and, what is of much greater importance, it contributed to make them better acquainted with themselves--it excited new enterprises--it educed latent talents--it stimulated to exertions unknown to our people before.

A long extent of coast was exposed to an enemy, powerful above every other on the ocean. His commanders threatened to lay waste our country with fire and sword, and, actually, in various instances, carried their menaces into execution. It became necessary, for our defense, to resist, by every practicable method, such a formidable foe.

It was conceived, by a most ingenious and enterprising citizen, that the power of Steam could be employed to propel a floating battery, carrying heavy guns, to the destruction of any hostile force that should hover on the shores, or enter the ports of our Atlantic frontier. The perfect and admirable success of his project for moving boats containing travelers and baggage by the same elastic agent, opened the way to its employment for carrying warriors and the apparatus for fighting.

The plan was submitted to the consideration of the executive of an enlightened government. Congress, influenced by the most liberal and patriotic spirit, appropriated money for the experiment, and the Navy Department, then conducted by the honorable William Jones, appointed commissioners to superintend the construction of a convenient vessel under the direction of ROBERT FULTON, the inventor, as engineer, and Messrs. Adam and Noah Brown, as naval constructors. The enterprise, from its commencement, and during a considerable part of its preparatory operations, was aided by the zealous co-operation of Major General Dearborn, then holding his head-quarters at the city of New York, as the officer commanding the third military district. The loss of his valuable counsel in conducting a work which he had maturely considered, and which he strongly recommended, was the consequence of his removal to another section of the Union, where his professional talents were specially required.

The keels of this steam-frigate were laid on the twentieth day of June, eighteen hundred and fourteen. The strictest blockade the enemy could enforce interrupted the coasting trade, and greatly enhanced the price of timber. The vigilance with which he guarded our coast against intercourse with foreign nations, rendered difficult the importation of copper and iron. The same impediment attended the supplies of coal heretofore brought to New York from Richmond and Liverpool. Lead, in like manner, was procured under additional disadvantages. These attempts of the enemy to frustrate the design, were vain and impotent. All the obstacles were surmounted. Scarcity of the necessary woods and metals were overcome by strenuous exertions; and all the blockading squadron could achieve, was not a disappointment in the undertaking, but merely an increase of the expense.

So, in respect to tradesmen and laborers, there was an extraordinary difficulty. Shipwrights had repaired to the lakes, for repelling the enemy, in such numbers, that, comparatively speaking, few were left on the seaboard. A large portion of the men who had been engaged in daily work, had enlisted as soldiers, and had marched under the banners of the nation to the defense of its rights--yet amidst the scarcity of hands, a sufficient number were procured for the purpose which the Commissioners had in charge. An increase of wages was the chief impediment, and this they were enabled practically to overcome.

By the exemplary combination of diligence and skill, on the part of the Engineer and Constructors, the business was so accelerated, that the vessel was launched on the twenty-ninth day of October, amidst the plaudits of an unusual number of citizens.

Measures were immediately taken to complete her equipment; the boiler, the engine, and the machinery were put on board with all possible expedition. Their weight and size far surpassed any thing that had been witnessed before among us.

The stores of artillery in New York not furnishing the number and kind of cannon which she was destined to carry, it became necessary to transport guns from Philadelphia. A prize, taken from the enemy, put some fit and excellent pieces at the disposal of the Navy Department. To avoid the danger of capture by the enemy's cruisers, these were carted over the miry roads of New Jersey. Twenty heavy cannon were thus conveyed by the strength of horses. Carriages of the most approved model were constructed, and every thing done to bring her into prompt action, as an efficient instrument of war.

About this time, an officer, pre-eminent for bravery and discipline, was commissioned by the government to her command. Prior to this event, it had been intended by the Commissioners to finish her conformably to the plan originally submitted to the Executive. She is a structure resting upon two boats and keels, separated from end to end by a canal fifteen feet wide, and sixty-six long. One boat contained the caldrons of copper to prepare her steam. The vast cylinder of iron, with its piston, levers, and wheels, occupied a part of its fellow; the great water-wheel revolved in the space between them; the main or gun-deck supported her armament, and was protected by a bulwark four feet ten inches thick, of solid timber. This was pierced by thirty port-holes, to enable as many thirty-two pounders to fire red hot balls; her upper or spar deck was plain, and she was to be propelled by her enginery alone.

It was the opinion of Captain Porter and Mr. Fulton, that the upper deck ought to be surrounded with a bulwark and stanchions--that two stout masts should be erected to support latteen sails--that there should be bowsprits for jibs, and that she should be rigged in a corresponding style. Under authorities so great, and with the expectation of being able to raise the blockade of New London, by destroying, taking, or routing the enemy's ships, all these additions were adopted and incorporated with the vessel.

It must here be observed, that during the exhaustion of the treasury, and the temporary depression of public credit, the Commissioners were exceedingly embarrassed--their payments were made in treasury notes, which they were positively instructed to negotiate at par. On several occasions even these were so long withheld, that the persons who had advanced materials and labor were importunate for payment, and silently discontented. To a certain extent, the Commissioners pledged their private credit. Notwithstanding all this, the men, at one time, actually broke off. The work was retarded, and her completion unavoidably deferred, to the great disappointment of the Commissioners, until winter rendered it impossible for her to act.

Under all this pressure, they, nevertheless, persevered in the important object confided to them. But their exertions were further retarded by the premature and unexpected death of the Engineer. The world was deprived of his invaluable labors before he had completed this favorite undertaking. They will not inquire, wherefore, in the dispensations of Divine Providence, he was not permitted to realize his grand conception. _His discoveries, however, survive for the benefit of mankind_, and will extend to unborn generations.

At length all matters were ready for a trial of the machinery to urge such a bulky vessel through the water. This essay was made on the first day of June, eighteen hundred and fifteen. She proved herself capable of opposing the wind, and of stemming the tide, of crossing currents, and of being steered among vessels riding at anchor, though the weather was boisterous and the water rough. Her performance demonstrated that the project was successful--no doubt remained that a floating battery, composed of heavy artillery, could be moved by steam. The Commissioners returned from the exercise of the day, satisfied that the vessel would answer the intended purpose, and consoled themselves that their care had been bestowed upon a worthy object.

But it was discovered, that various alterations were necessary. Guided by the light of experience, they caused some errors to be corrected, and some defects to be supplied. She was prepared for a second voyage with all practicable speed.

On the fourth of July she was again put in action. She performed a trip to the ocean, eastward of Sandy Hook, and back again, a distance of fifty-three miles, in eight hours and twenty minutes. A part of this time she had the tide against her, and had no assistance whatever from sails. Of the gentlemen who formed the company invited to witness the experiment, not one entertained a doubt of her fitness for the intended purpose.

Additional expedients were, notwithstanding, necessary to be sought for quickening and directing her motion. These were devised and executed with all possible care.

Suitable arrangements having been made, a third trial of her powers was attempted on the eleventh day of September, with the weight of twenty-six of her long and ponderous guns, and a considerable quantity of ammunition and stores on board; her draft of water was short of eleven feet. She changed her course by inverting the motion of the wheel, without the necessity of putting about. She fired salutes as she passed the forts, and she overcame the resistance of the wind and tide in her progress down the bay. She performed beautiful man[oe]uvres around the United States' Frigate JAVA, then at anchor near the light-house. She moved with remarkable celerity, and she was perfectly obedient to her double helm. It was observed that the explosion of powder produced very little concussion. The machinery was not affected by it in the smallest degree. Her progress, during the firing, was steady and uninterrupted. On the most accurate calculations, derived from heaving the log, her average velocity was five and a-half miles per hour. Notwithstanding the resistance of currents, she was found to make headway at the rate of two miles an hour against the ebb of the East River, running three and a-half knots. The day's exercise was satisfactory to the respectable company who attended, beyond their utmost expectations. It was universally agreed that we now possessed a new auxiliary against every maratime invader. The City of New York, exposed as it is, was considered as having the means of rendering itself invulnerable. The Delaware, Chesapeake, Long Island Sound, and every other bay and harbor in the nation, may be protected by the same tremendous power.

Among the inconveniences observable during the experiment, was the heat endured by the men who attended the fires. To enable a correct judgment to be formed on this point, one of the Commissioners (Dr. Mitchel) descended and examined, by a thermometer, the temperature of the hold, between the two boilers. The quicksilver, exposed to the radiant heat of the burning fuel, rose to one hundred and sixteen degrees of Fahrenheit's scale. Though exposed thus to its intensity, he experienced no indisposition afterwards. The analogy of potteries, forges, glass-houses, kitchens, and other places, where laborers are habitually exposed to high heats, is familiar to persons of business and of reflection. In all such occupations, the men, by proper relays, perform their services perfectly well.

The Government, however, will understand that the hold of the present vessel could be rendered cooler by other apertures for the admission of air, and that on building another steam frigate, the comfort of the firemen might be provided for, as in the ordinary steamboats.

The Commissioners congratulate the Government and the nation on the event of this noble project. Honorable alike, to its author and its patrons, it constitutes an era in warfare and the arts. The arrival of peace, indeed, has disappointed the expectations of conducting her to battle. That last and conclusive act of showing her superiority in combat, has not been in the power of the Commissioners to make.

If a continuance of tranquillity should be our lot, and this steam vessel of war be not required for the public defense, the nation may rejoice that the fact we have ascertained is of incalculably greater value than the expenditure--and that if the present structure should perish, we have the information never to perish, how, on a future emergency, others may be built. The requisite variations will be dictated by circumstances.

Owing to the cessation of hostilities, it has been deemed inexpedient to finish and equip her as for immediate and active employ. In a few weeks every thing that is incomplete could receive the proper adjustment.

After so much has been done, and with such encouraging results, it becomes the Commissioners to recommend that the steam frigate be officered and manned for discipline and practice. A discreet commander, with a selected crew, could acquire experience in the mode of navigating this peculiar vessel. The supplies of fuel, the tending of the fire, the replenishing of the expended water, the management of the mechanism, the heating of shot, the exercise of the guns, and various matters, can only become familiar by use. It is highly important that a portion of seamen and marines should be versed in the order and economy of the steam frigate. They will augment, diffuse, and perpetuate knowledge. When, in process of time, another war shall call for more structures of this kind, men, regularly trained to her tactics, may be dispatched to the several stations where they may be wanted. If, on any such disposition, the Government should desire a good and faithful agent, the Commissioners recommend Captain Obed Smith to notice, as a person who has ably performed the duties of inspector from the beginning to the end of the concern.

Annexed to the report, you will find, Sir, several statements explanatory of the subject. A separate report of our colleague, the honorable Oliver Wolcott, whose removal from New York precluded him from attending to the latter part of the business, with his accustomed zeal and fidelity, is herewith presented. A drawing of her form and appearance, by Mr. Morgan, as being like to give satisfaction to the department, is also subjoined, as are likewise an inventory of her furniture and effects, and an account of the timber and metals consolidated in her fabric.

It is hoped these communications will evince the pains taken by the Commissioners, to execute the honorable and responsible trust reposed in them by the Government.

SAMUEL L. MITCHEL.
THOMAS MORRIS.
HENRY RUTGERS.

* * * * *

FOOTNOTES

[1] _The American Neptune_ (1946), vol. 6, pp. 253-274.

[2] _The American Neptune_ (1944), vol. 4, pp. 327-329.

[3] New York, 1853, pp. 13-17.

[4] Pittsburgh, 1896, pp. 8-16.

[5] See pages 172 through 176 for this report, which is reproduced
from CHARLES B. STUART, _Naval and Mail Steamers of the United
States_ (New York, 1853), app., pp. 155-159.

[6] National Archives, Navy Records Plans, 80-7-14; and HOWARD I.
CHAPELLE, _History of the American Sailing Navy_ (New York: W.
W. Norton & Co., 1949), pp. 293-295.

[7] National Archives, Navy Records Plans, 80-7-9; and CHAPELLE,
_History of the American Sailing Navy_, pp. 226, 228.

[8] National Archives, Navy Records Plans, 80-7-15.

[9] National Archives, Naval Records Collection, Miscellaneous
Letters, 1819, II.

[10] See p. 169, reproduced from CHARLES B. STUART, _Naval and Mail
Steamers of the United States_ (New York, 1853), p. 15.

[11] JEAN BAPTISTE MARESTIER, _Mémoire sur les bateaux à vapeur des
États-Unis d'Amérique, avec un appendice sur diverses machines
relatives à la Marine_ (Paris: L'imprimerie Royal, 1824).

[12] 1820-1823, vol. 7, p. 437.

[13] _Annales de l'industrie nationale et étrangère, ou Mercure
Technologique_ (Paris, 1822), pp. 760-762.

[14] January 27, 1823, vol. 7, pp. 436-438.

[15] January-March 1935, vol. 61, pp. 322-328.

[16] HOWARD I. CHAPELLE, _American Small Sailing Craft_ (New York:
W. W. Norton & Co., Inc., 1951), pp. 29, 31.

[17] Newport News, Va.: The Mariners' Museum, 1937, p. 23.

[18] Indianapolis, Ind.: Bobbs Merrill, 1932, p. 291.

[19] HENRY WILLIAM EDWARD, _The Double Bottom or Twin Hulled Ship of
Sir William Petty_ (Oxford: The Roxburghe Club, 1931).

[20] Publication No. 5 (Newport News: The Mariners' Museum, 1939),
p. 22.

* * * * *

Typographical Corrections

Pg. 152: "the _Simon & Jude_, later called _Invention I_" (was "latter").

* * * * *

CONTRIBUTIONS FROM
THE MUSEUM OF HISTORY AND TECHNOLOGY:

PAPER 40

HISTORY OF PHOSPHORUS

_Eduard Farber_

THE ELEMENT FROM ANIMALS AND PLANTS 178

EARLY USES 181

CHEMICAL CONSTITUTION OF PHOSPHORIC ACIDS 182

PHOSPHATES AS PLANT NUTRIENTS 185

FROM INORGANIC TO ORGANIC PHOSPHATES 187

PHOSPHATIDES AND PHOSPHAGENS 189

NUCLEIN AND NUCLEIC ACIDS 192

PHOSPHATES IN BIOLOGICAL PROCESSES 197

MEDICINES AND POISONS 198

_Eduard Farber_

HISTORY OF PHOSPHORUS

_The "cold light" produced by phosphorus caused it to be
considered a miraculous chemical for a long time after its
discovery, about 1669. During the intervening three centuries
numerous other chemical miracles have been found, yet
phosphorus retains a special aura of universal importance in
chemistry. Many investigators have occupied themselves with
this element and its diverse chemical compounds. Further
enlightenment and insight into the ways of nature can be
expected from these efforts._

_Not only is the story of phosphorus a major drama in the
history of chemistry; it also illustrates, in a spectacular
example, the growth of this science through the discovery of
connections between apparently unrelated phenomena, and the
continuous interplay between basic science and the search for
practical usage._

THE AUTHOR: _Eduard Farber is a research professor at American
University, Washington, D.C., and has been associated with the
Smithsonian Institution as a consultant in chemistry._

When phosphorus was discovered, nearly three centuries ago, it was considered a miraculous thing. The only event that provoked a similar emotion was the discovery of radium more than two centuries later. The excitement about the _Phosphorus igneus_, Boyle's _Icy Noctiluca_, was slowly replaced by, or converted into, chemical research. Yet, if we would allow room for emotion in research, we could still be excited about the wondrous substance that chemical and biological work continues to reveal as vitally important. It is a fundamental plant nutrient, an essential part in nerve and brain substance, a decisive factor in muscle action and cell growth, and also a component in fast-acting, powerful poisons. The importance of phosphorus was gradually recognized and the means by which this took place are characteristic and similar to other developments in the history of science. This paper was written in order to summarize these various means which led to the highly complex ways of present research.

The Element from Animals and Plants

It was a little late to search for the philosophers' stone in 1669, yet it was in such a search that phosphorus was discovered. Wilhelm Homberg (1652-1715) described it in the following manner: Brand, "a man little known, of low birth, with a bizarre and mysterious nature in all he did, found this luminous matter while searching for something else. He was a glassmaker by profession, but he had abandoned it in order to be free for the pursuit of the philosophical stone with which he was engrossed. Having put it into his mind that the secret of the philosophical stone consisted in the preparation of urine, this man worked in all kinds of manners and for a very long time without finding anything. Finally, in the year 1669, after a strong distillation of urine, he found in the recipient a luminant matter that has since been called phosphorus. He showed it to some of his friends, among them Mister Kunkel [sic]."[1]

Neither the name nor the phenomenon were really new. Organic phosphorescent materials were known to Aristotle, and a lithophosphorus was the subject of a book published in 1640, based on a discovery made by a shoemaker, Vicenzo Casciarolo, on a mountain-side near Bologna in 1630.[2] Was the substance new which Brand showed to his friends? Johann Gottfried Leonhardi quotes a book of 1689 in which the author, Kletwich, claims that this phosphorus had already been known to Fernelius, the court physician of King Henri II of France (1154-1189).[3] To the same period belongs the "Ordinatio Alchid Bechil Saraceni philosophi," in which Ferdinand Hoefer found a distillation of urine with clay and carbonaceous material described, and the resulting product named escarbuncle.[4] It would be worth looking for this source; although Bechil would still remain an entirely unsuccessful predecessor, it does seem strange that in all the distillations of arbitrary mixtures, the conditions should never before 1669 have been right for the formation and the observation of phosphorus.

For Brand's contemporaries at least, the discovery was new and exciting. The philosopher Gottfried Wilhelm von Leibniz (1646-1716) considered it important enough to devote some of his time (between his work as librarian in Hanover and Wolfenbüttel, his efforts to reunite the Protestant and the Catholic churches, and his duties as Privy Councellor in what we would call a Department of Justice) to a history of phosphorus. This friend of Huygens and Boyle tried to prove that Kunckel was not justified in claiming the discovery for himself.[5] Since then, it has been shown that Johann Kunckel (1630-1703) actually worked out the method which neither Brand nor his friend Kraft wanted to disclose. Boyle also developed a method independently, published it, and instructed Gottfried Hankwitz in the technique. Later on, Jean Hellot (1685-1765) gave a meticulous description of the details and a long survey of the literature.[6]

To obtain phosphorus, a good proportion of coal (regarded as a type of phlogiston) was added to urine, previously thickened by evaporation and preferably after putrefaction, and the mixture was heated to the highest attainable temperature. It was obvious that phlogiston entered into the composition of the distillation product. The question remained whether this product was generated _de novo_. In his research of 1743 to 1746, Andreas Sigismund Marggraf (1709-1782) provided the answer. He found the new substance in edible plant seeds, and he concluded that it enters the human system through the plant food, to be excreted later in the urine. He did not convince all the chemists with his reasoning. In 1789, Macquer wrote: "There are some who, even at this time, hold that the phosphorical ('phosphorische') acid generates itself in the animals and who consider this to be the 'animalistic acid.'"[7]

Although Marggraf was more advanced in his arguments than these chemists, yet he was a child of his time. The luminescent and combustible, almost wax-like substance impressed him greatly. "My thoughts about the unexpected generation of light and fire out of water, fine earth, and phlogiston I reserve to describe at a later time." These thoughts went so far as to connect the new marvel with alchemical wonder tales. When Marggraf used the "essential salt of urine," also called _sal microcosmicum_, and admixed silver chloride ("horny silver") to it for the distillation of phosphorus, he expected "a partial conversion of silver by phlogiston and the added fine vitrifiable earth, but no trace of a more noble metal appeared."[8]

Robert Boyle had already found that the burning of phosphorus produced an acid. He identified it by taste and by its influence on colored plant extracts serving as "indicators." Hankwitz[9] described methods for obtaining this acid, and Marggraf showed its chemical peculiarities. They did not necessarily establish phosphorus as a new element. To do that was not as important, at that time, as to conjecture on analogies with known substances. Underlying all its unique characteristics was the analogy of phosphorus with sulfur. Like sulfur, phosphorus can burn in two different ways, either slowly or more violently, and form two different acids. The analogy can, therefore, be extended to explain the results in both groups in the same way. In the process of burning, the combustible component is removed, and the acid originally combined with the combustible is set free. Whether the analogy should be pursued even further remained doubtful, although some suspicion lingered on for a while that phosphoric acid might actually be a modified sulfuric acid. Analogies and suspicions like these were needed to formulate new questions and stimulate new experiments. They are cited here for their important positive value in the historical development, and not for the purpose of showing how wrong these chemists were from our point of view, a point of view which they helped to create.

The widespread interest in the burning of sulfur and of phosphorus, naturally, caught Lavoisier's attention. In his first volume of _Opuscules Physiques et Chimiques_ (1774), he devoted 20 pages to his experiments on phosphorus. He amplified them a few years later[10] when he attributed the combustion to a combination of phosphorus with the "eminently respirable" part of air. In the _Méthode de Nomenclature Chimique_ of 1787, the column of "undecomposed substances" lists sulfur as the "radical sulfurique," and phosphorus, correspondingly, as the "radical phosphorique." The acids are now shown to be compounds of the "undecomposed" radicals, the complete reversion of the previous concept of this relationship. A part of the old analogy remained as far as the acids are concerned: sulfuric acid corresponds to phosphoric; sulfurous acid to phosphorous acid with less oxygen than in the former.[11]

Early Uses

In the 18th century, phosphorus was a costly material. It was produced mostly for display and to satisfy curiosity. Guillaume François Rouelle (1703-1770) demonstrated the process in his lectures, and, as Macquer reports, he "very often" succeeded in making it.[12] Robert Boyle had the idea of using phosphorus as a light for underwater divers.[13] A century later, "instant lights" were sold, with molten phosphorus as the "igniter," but they proved cumbersome and unreliable.[14] Because white phosphorus is highly poisonous, an active development of the use in matches occurred only after the conversion of the white modification into the red had been studied by Émile Kopp (1844), by Wilhelm Hittorf (1824-1914) and, in its practical application, by Anton Schrötter (1802-1875).[15]

The most exciting early use, however, was in medicine. It is not surprising that such a use was sought at that time. Any new material immediately became the hope of ailing mankind--and of striving inventors.[16] Phosphorus was prescribed, in liniments with fatty oils or as solution in alcohol and ether, for external and internal application. A certain Dr. Kramer found it efficient against epilepsy and melancholia (1730). A Professor Hartmann recommended it against cramps.[17] However, in the growing production of phosphorus for matches, the workers experienced the poisonous effects. In the plant of Black and Bell at Stratford, this was prevented by inhaling turpentine. Experiments on dogs were carried out to show that poisoning by phosphorus could be remedied through oil of turpentine.[18]

Chemical Constitution of Phosphoric Acids

In a long article on phosphorus, Edmond Willm wrote in 1876: "For a century, urine was the only source from which phosphorus was obtained. After Gahn, in 1769, recognized the presence of phosphoric acid in bones, Scheele indicated the procedure for making phosphorus from them."[19] Actually, Gahn used at first hartshorn (_Cornu cervi ustum_), and Scheele doubted, until he checked it himself, that his esteemed friend was right. A few years later, Scheele corrected Gahn's assumption that the _sal microcosmicum_ was an ammonia salt; instead, it is "a tertiary neutral salt, consisting of _alkali minerali fixo_ (i.e., sodium), _alkali volatili_, and _acido phosphori_."[20]

In the years after 1770, phosphorus was discovered in bones and many other parts of various animals. Treatment with sulfuric acid decomposed these materials into a solid residue and dissolved phosphoric acid. Many salts of this acid were produced in crystalline form. Heat resistance had been considered one of the outstanding characteristics of phosphoric acid. Now, however, in the processes of drying and heating certain phosphates, it became clear that three kinds of phosphoric acids could be produced: _ortho_, _pyro_, and _meta_.

Berzelius cited these acids as examples of compounds which are ISOMERIC. This word was intended to designate compounds which contain the same number of atoms of the same elements but combined in different manners, thereby explaining their different chemical properties and crystal forms. It was in 1830 that Berzelius propounded this companion of the concept, ISOMORPHISM, which was to collect all cases of equal crystal form in compounds in which equal numbers of atoms of different elements are put together in the same manner. Together, the two concepts of isomerism and isomorphism seemed to cover all the known exceptions from the simplest assumption as to specificity and chemical composition.

However, only a few years later Thomas Graham (1805-1869) proved that the three phosphoric acids are not isomeric. He used the proportion of 2 P to 5 O in the oxide which Berzelius had thought justified at least until "an example of the contrary could be sufficiently established."[21] Refining the techniques of Gay-Lussac (1816) and several other investigators, Graham characterized the three phosphoric acids as "a terphosphate, a biphosphate, and phosphate of water." Actually, this was the wrong terminology for what he meant and formulated as trihydrate, bihydrate, and monohydrate of phosphorus oxide. In his manner of writing the formulas, each dot over the symbol for the element was to indicate an atom of oxygen; thus, he wrote:

... :: .. ... . .
H^{3} P H^{2} P and H P.[22]

Graham had come to this understanding of the phosphoric acids through his previous studies of "Alcoates, definite compounds of Salts and Alcohol analogous to the Hydrates" (1831). Liebig started from analogies he saw with certain organic acids when he formulated the phosphoric acids with a constant proportion of water (aq.) and varying proportions of "phosphoric acid" (P) as follows:

2 P 3 aq. phosphoric acid
3 P 3 aq. pyrophosphoric acid
6 P 3 aq. metaphosphoric acid.

Salts are formed when a "basis," i.e., a metal oxide, replaces water. When potassium-acid sulfate is neutralized by sodium base, the acid-salt divides into Glauber's salt and potassium sulfate, which proves the acid-salt to be a mixture of the neutral salt with its acid. Sodium-acid phosphate behaves quite differently. After neutralization by a potassium "base" (hydroxide), the salt does not split up; a uniform sodium-potassium phosphate is obtained. Therefore, phosphoric acid is truly three-basic![23]

This result has later been confirmed, but the analogy by means of which it had been obtained was very weak, in certain parts quite wrong.

The acids from the two lower oxides of phosphorus were also considered as three-basic. Adolphe Wurtz (1817-1884) formulated them in 1846, according to the theory of chemical types:

(PO)···
O^{3} phosphoric acid
H^{3}

(PHO)··
O^{2} phosphorus acid
H^{2}

(PH^{2}O)·
O hypophosphorous acid.[24]
H

Further proof for these constitutions was sought in the study of the esters formed when the acids react with alcohols.

Among the analogies and generalizations by which the research on phosphoric acid was supported, and to the results of which it contributed a full share, was the new theory of acids. Not oxygen, Lavoisier's general acidifier, but reactive hydrogen determines the character of acids. In this brief survey, it seems sufficient just to mention this connection without describing it in detail.

The study of phosphoric acids led to important new concepts in theoretical chemistry. The finding of polybasicity was extended to other acids and formed the model that helped to recognize the polyfunctionality in other compounds, like alcohols and amines. The hydrogen theory of acids was fundamental for further advance. In another dimension, it is particularly interesting to see that large-scale applications followed almost immediately and directly from the new theoretical insight. The first and foremost of these applications was in agriculture.

Phosphates as Plant Nutrients

One hundred years after the discovery of "cold light," the presence of phosphorus in plants and animals was ascertained, and its form was established as a compound of phosphoric acid. This knowledge had little practical effect until the "nature" of the acid, in its various forms, was explained through the work of Thomas Graham. From it, there started a considerable technical development.

At about that time (1833), the Duke of Richmond proved that the fertilizing value of bones resided not in the gelatin, nor in the calcium, but in the phosphoric acid. Thus, he confirmed what Théodore de Saussure had said in 1804, that "we have no reason to believe" that plants can exist without phosphorus. Unknowingly at first, the farmer had supplied this element by means of the organic fertilizers he used: manure, excrements, bones, and horns. Now, with the value of phosphorus known, a search began for mineral phosphates to be applied as fertilizers. Jean Baptiste Boussingault (1802-1887), an agricultural chemist in Lyons, traveled to Peru to see the guano deposits. Garcilaso de la Vega (ca. 1540 to ca. 1616) noted in his history of Peru (1604) that guano was used by the Incas as a fertilizer. Two hundred years later, Alexander von Humboldt revived this knowledge, and Humphry Davy wrote about the benefits of guano to the soil. Yet, the application of this fertilizer developed only slowly, until Justus Liebig sang its praise. Imports into England rose and far exceeded those into France where, between 1857 and 1867, about 50,000 tons were annually received.

The other great advance in the use of phosphatic plant nutrients started with Liebig's recommendation (1840) to treat bones with sulfuric acid for solubilization. This idea was not entirely new; since 1832, a production of a "superphosphate" from bones and sulfuric acid had been in progress at Prague. At Rothamsted in 1842, John Bennet Lawes obtained a patent on the manufacture of superphosphate. Other manufactures in England followed and were successful, although James Muspratt (1793-1886) at Newton lost much time and "some thousands of pounds" on Liebig's idea of a "mineral manure."

It was difficult enough to establish the efficacy of bones and artificially produced phosphates in promoting the growth of plants under special conditions of soils and climate; therefore, the question as to the action of phosphates in the growing plant was not even seriously formulated at that time. The beneficial effects were obvious enough to increase the use of phosphates as plant nutrients and to call for new sources of supply. Active developments of phosphate mining and treating started in South Carolina in 1867, and in Florida in 1888.[25]

In a reciprocal action, more phosphate application to soils stimulated increasing research on the conditions and reactions obtaining in the complex and varying compositions called soil. The findings of bacteriologists made it clear that physics and chemistry had to be amplified by biology for a real understanding of fertilizer effects. After 1900, for example, Julius Stoklasa (1857-1936) pointed out that bacterial action in soil solubilizes water-insoluble phosphates and makes them available to the plants.[26]

The insight into the importance of phosphorus in organisms, especially since Liebig's time, is reflected in the work of Friedrich Nietzsche (1844-1900). This "re-valuator of all values" who modestly said of himself: "I am dynamite!" once explained the human temperaments as caused by the inorganic salts they contain: "The differences in temperament are perhaps caused more by the different distribution and quantities of the inorganic salts than by everything else. Bilious people have too little sodium sulfate, the melancholics are lacking in potassium sulfate and phosphate; too little calcium phosphate in the phlegmatics. Courageous natures have an excess of iron phosphate." (See volume 12 of _Nietzsche's Works_, edit. Naumann-Kröner, Leipzig, 1886.) In this strange association of inorganic salts with human temperaments, the role of iron phosphate as a producer of courage is particularly interesting. What would a modern philosopher conclude if he followed the development of insight into the composition and function of complex phosphate compounds in organisms?

From Inorganic to Organic Phosphates

By the middle of the 19th century, the source of phosphorus in natural phosphates and the chemistry of its oxidation products had been established. The main difficulty that had to be overcome was that these oxidation products existed in so many forms, not only several stages of oxidation, but, in addition, aggregations and condensations of the phosphoric acids. Once the fundamental chemistry of these acids was elucidated, the attention of chemists and physiologists turned to the task of finding the actual state in which phosphorus compounds were present in the organisms. It had been a great advance when it had been shown that plants need phosphates in their soil. This led to the next question concerning the materials in the body of the plant for which phosphates were being used and into which they were incorporated. Similarly, the knowledge that animals attain their phosphates from the digested plant food called, in the next step of scientific inquiry, for information on the nature of phosphates produced from this source.

The method used in this inquiry was to subject anatomically separated parts of the organisms to chemical separations. The means for such separations had to be more gentle than the strong heat and destructive chemicals that had been considered adequate up to then. The interpretation of the new results naturally relied on the general advance of chemistry, the development of new methods for isolating substances of little stability, of new concepts concerning the arrangements of atoms in the molecules, and of new apparatus to measure their rates of change.

In the system of chemistry, as it developed in the first half of the 19th century, the new development can be characterized as the turn from inorganic to organic phosphates, from the substance of minerals and strong chemical interactions to the components in which phosphate groups remained combined with carbon-containing substances.

Figure 1 [shown here] is a vertical section of the furnace, and Fig. 2 is a diagram to illustrate the means for regulating the electro-motive force or quantity of current across the furnace.

F is the furnace containing the charge to be treated. It has an inlet-hopper at _a_, with slides AA, by which the charge can be admitted without opening communication between the interior of the furnace and the outer air.

B is a screw conveyer by which the charge is pushed forward into the furnace.

_c´c´_ are the electrodes, consisting of blocks or cylinders or the like of carbon fixed in metal socket-pieces _c c_, to which the electric-circuit wires _d_ from the dynamo D are affixed. The current, as aforesaid, may be either continuous or alternating. _c^{2}c^{2}_ are rods of metal or carbon, which are used to establish the electric circuit through the furnace, the said rods being inserted into holes in conductors _c^{3}_ (in contact with the socket-pieces _c_) and in the furnace, as shown.

_g_ is the outlet for the gas or vapor, _h_ the slag-tap hole, and _x_ the opening for manipulating the charge, the said openings being closed by clay or otherwise when the furnace is at work.

I use coke or other form of carbon in the charge between the electrodes _c´_, the said coke being in contact with the said electrodes, so that complete incandescence is insured.

A means for varying the electro-motive force or quantity of current across the furnace with the varying resistance of the charge is illustrated by the diagram, Fig. 2. _c´ c^{2}_ indicate the electrodes in the furnace, as in Fig. 1, and D is the dynamo and T its terminals. E represents the exciting-circuit. R R are resistances, and R S is the resistance-switch, which is operated to put in more or less resistance at R as the resistance of the charge in the furnace lessens or increases. This switch may be automatically operated, and a suitable arrangement for the purpose is a current-regulator such as is described in the specification of English Letters Patent No. 14,504, of September 14, 1889, granted to William Henry Douglas and Thomas Hugh Parker.]

T. PARKER.
ELECTRICAL FURNACE.

Patented Sept. 13, 1892.

FIG. 1.]

_Inventor
Thomas Parker_

_By his attorneys
Howson and Howson_

_Witnesses:
George Baumann
John Revell_]

Phosphatides and Phosphagens

The important phosphorus compounds in organisms are much more complex than the simple salts, to which Nietzsche attributed such influence on man's character. Long before he wrote, it was known that phosphoric acid combines not only with inorganic bases to form salts, but with alcohols to form esters. In the middle of the 19th century, Théophile Juste Pelouze (1807-1867) extended this knowledge to an ester of glycerol. This proved to be significant in several respects. Glycerol had been shown by Michel Chevreul (1786-1889) as the substance in fats that is released in the process of soap boiling, when the fatty acids are converted into their salts. That it has the nature of an alcohol had been demonstrated by Marcellin Berthelot. Instead of one "alcoholic" hydroxyl group, OH, like ethanol (the alcohol of fermentation), or two hydroxyl groups (like ethylene glycol), glycerol contains three such groups. It was the only "natural" alcohol known at that time. That this alcohol would combine with phosphoric acid could be predicted, but that the ester, as obtained by Pelouze, still contained free acidic functions and formed a water-soluble barium salt was a new experience.

ALCOHOLIC FERMENTATION

(C_{6}H_{10}O_{5})_{_n_} C_{6}H_{12}O_{6} C_{6}H_{12}O_{6}
glycogen glucose fructose
^| ^| ^|
|| H_{3}PO_{4} || <-- ATP || <--ATP
|v |v |v
---------------+ ------+
H--C--OPO_{3}H_{2}| H--C--OH | H _{2}C--OH
| | | | |
H--C--OH | H--C--OH | C--(OH)--+
| | | | | |
HO--C--H O <==> HO--C--H O <=======> HO--C--H |
| | | | | O
H--C--OH | H--C--OH | H--C--OH |
| | | | | |
H--C--------------+ H--C-----+ H--C--------+
| | |
CH_{2}OH H_{2}C--OPO_{3}H_{2}+ADP H_{2}C--OPO_{3}H_{2}+ADP

glucose-1-phosphate glucose-6-phosphate fructose-6-phosphate
(Cori-ester) (Robison-ester) (Neuberg-ester)
^ |
| | <-- ATP
+----| |
| +------|
| |
| v
H_{2}C--OPO_{3}H_{2}
|
C(OH)--+
| |
HO--C--H |
fructose-1,6-diphosphate | O
(Harden-Young-ester) H--C--OH |
| |
H--C------+
|
H_{2}C--OPO_{3}H_{2} + ADP
^|
|| O
|| //
CH_{2}OPO_{3}H_{2} || CH
| |v | 3-phosphoglycer-aldehyde
dihydroxyacetone-phosphate C=O <=============> CHOH (Fischer-ester)
| |
CH_{2}OH CH_{2}OPO_{3}H_{2}
|| + coenzyme + H_{3}PO_{4}
O=C--OPO_{3}H_{2}
|
1,3-diphosphoglyceric acid CHOH + dihydro-coenzyme
(Negelein-ester) |
CH_{2}OPO_{3}H
^|
ADP --> ||
|| O
|v//
C--OH
| +---+
3-phosphoglyceric acid CHOH + |ATP|
(Nilsson-ester) | +---+
CH_{2}OPO_{3}H_{2}
^|
|v
COOH
2-phosphoglyceric acid |
CHOPO_{3}H_{2}
|
CH_{2}OH
^|
|v
COOH
|
phosphopyruvic acid COPO_{3}H_{2}
(enol-) ||
CH_2
ADP --> ||
COOH
+------+ | +---+
|CO_{2}| + CH_3CHO <-------- C=O + |ATP|
+------+ acetaldehyde | +---+
carbon | CH_{3}
dioxide | + dihydro-coenzyme pyruvic acid
|
v
+----------------+
| CH_{3}CH_{2}OH | + coenzyme
+----------------+
ethyl alcohol

Shortly after this experience had been gained, it became valuable for understanding the chemical nature of a new substance extracted from a natural organ. This substance was named lecithin by its discoverer, Nicolas Théodore Gobley[27] (1811-1876), because he obtained it from egg yolk (in Greek, _lékidos_). He used ether and alcohol for this extraction. Had he used water and mineral acid instead, he would not have found lecithin, but only its components. As Gobley and, slightly later, Oscar Liebreich (1839-1908), subjected lecithin to treatment with boiling water and acid, they separated it into three parts. One of them was the glycerophosphoric acid of Pelouze, the second was the well-known stearic acid of Chevreul, but the third was somewhat mysterious. This third substance was the same as one previously noticed when nerves had been subjected to an extraction by boiling water and acid and, therefore, called nerve-substance or neurine. Adolf Friedrich Strecker (1822-1871) established the identity of this neurine with a product he had extracted from bile and which went under the name of choline. Adolphe Wurtz (1817-1884) succeeded in synthesizing this substance from ethylene oxide, CH_2.O.CH_2 and trimethylamine N(CH_3)_3.[28] Thus, all three parts were identified, and Strecker put them together to construct a chemical formula for lecithin, glycerophosphoric acid combined with a fatty acid and with choline (a hydrate of neurine).

{ OH }
N { (CH_3)_3 } Choline
{ C_2H_4O }

C_18H_33O_2 } HO }
} } PO
C_16H_31O_2 } C_3H_5O }

Fatty Acids Glycerophosphate
\--------v-------/
Lecithin
according to Strecker

This formula was not quite correct. Richard Willstätter showed that an internal neutralization takes place between the amino group and the free acidic residue. This is expressed in his lecithin formula of 1918.

CH_{2}·O·R
|
CH_{2}·O·R_2
|
| O·CH_{2}·CH_{2}
| / \
CH_{2}·O--P=O N(CH_{3})_{3}
\ /
\---O----/

When the aim was to distill elementary phosphorus out of an organic material, it did not matter whether this was fresh or putrified. For obtaining lecithin out of egg yolk and similar materials, it was essential to use it in fresh condition. Otherwise, enzymes would have decomposed it. Through more recent work, four enzymes have been separated, which act specifically in decomposing lecithin. Enzyme A removes one fatty acid and leaves a complex residue, called lysolecithin, intact. Enzyme B attacks this residue and splits off the remaining fatty acid group from it, enzyme C liberates only the choline from lecithin, and enzyme D opens lecithin at the ester bond between glycerol and phosphoric acid. This is shown in the following diagram.

ENZYMATIC SPLITTING OF LECITHINS

ENZYME SUBSTRATE PRODUCTS

A Lecithin Lysolecithin and fatty
acids.

B Lysolecithin Glycero-phospho-choline
and fatty acids.

C Lecithin Phosphatidic acid and
choline.

D Lecithin Phosphoryl choline and
diglyceride.

Several fatty acids can be present in lecithin from various sources: palmitic and oleic acid, besides the stearic acid which at first had been thought the only one involved. In another group of extracts from brain or nerve tissue, amino-ethanol H_{2}NCH_{2}CH_{2}OH is found instead of the choline of lecithin. The variations include the alcohol, to which the fatty acids and choline phosphate are attached, for example, glycerol can be replaced by the so-called meat-sugar, inositol, which has six hydroxyl groups in its hexagon-shaped molecule C_{6}H_{6}(OH)_{6}.

The generally similar behavior of these phosphate-and fat-containing substances was emphasized by Ludwig Thudichum (1829-1901). He coined the name phosphatides for this group of substances from seeds and nerves.[29] His work on the phosphates in brain substance aroused particular interest. When William Crookes drew his highly imaginative picture of an "evolution" of the chemical elements, he put into it "phosphorus for the brain, salt for the sea, clay for the solid earth...."[30] But phosphatides occur in many places of organisms, in bacteria, in leaves and roots of plants, in fat and tissues of animals. And where phosphatides are found, there are also enzymes that specifically act on them. They are called phosphatases to imply that they split the phosphatides. In addition, enzymes are present, which transfer phosphate groups from one compound to another. They are more abundant in seeds of high fat content than in the more starch-containing seeds, but even potatoes and orange juice have phosphatases.[31]

Thus, from phosphatides, phosphoric acid is generated, and they could also be called phosphagens. Since 1926, however, the name phosphagens has been reserved for a group of organic substances that release their phosphoric acid very readily. The link between phosphorus and carbon is provided by oxygen in the phosphatides, by nitrogen in the phosphagens. In vertebrates, the basis for the phosphoric acid is creatine, whereas invertebrates have arginine instead.

H OH OH
| / /
N--P=O NH--P=O
/ \ / \
C=NH OH C=NH OH
\ \
N--CH_{2}COOH NH
| |
CH_{3} CH_{2}
|
Creatine phosphate CH_{2}
|
CH_{2}
|
CHNH_{2}
|
COOH

Arginine phosphate

Nuclein and Nucleic Acids

All parts of an organism are essential for life. Only with this in mind does it make sense to say that the most important part of the cell is its nucleus. From the nuclei of cells in pus and in salmon sperm, Johann Friedrich Miescher (1811-1887) obtained a peculiar kind of substance, which he named nuclein (1868). Its phosphate content was easily discovered, but to find the exact proportions and the nature of the other components required special methods of separation from phosphatides and other proteins. It was difficult to develop such methods at a time when little was known about the properties, and particularly the stability, of a nuclein. For preparing nuclein from yeast cells, Felix Hoppe-Seyler (1825-1895) described the following details: Yeast is dispersed in water to extract soluble materials, like salts or sugars. After a few hours, the insoluble material is separated, washed once more with water, and then extracted with a very dilute solution of sodium hydroxide. The slightly alkaline solution, freed from insoluble residues, is slowly added to a weak hydrochloric acid. A precipitate forms which is separated by filtration, washed with dilute acid, then with cold alcohol, and finally extracted by boiling alcohol. The dried residue is the nuclein.[32] It contains six percent phosphorus. A little more washing with water, a slightly longer treatment with acid or alcohol gives products of lower phosphorus content. Many experimental variations were necessary to establish the procedure that leads to purification without alteration of the natural substance.

This was also true for the methods of chemical degradation, carried out in order to find the components of nucleins in their highest state of natural complexity. It was learned for example, that the special kind of carbohydrate present in nucleins was very susceptible to change under the conditions of hydrolysis by acids. Phoebus Aaron Theodor Levine (1869-1940), therefore, used the digestion by a living organism. With E. S. London, he introduced a solution of nucleic acid into, e.g., the gastrointestinal segment of a dog through a gastric fistula and withdrew the product of digestion through an intestinal fistula. Fortunately, the products obtained in such degradations were not new in themselves. The carbohydrate in this nucleic acid proved to be identical with D-ribose, which Emil Fischer had artificially made from arabinose and named ribose to indicate this relationship (1891). The nitrogenous products of the degradation were identical with substances previously prepared in the long study of uric acid. In the course of this study, Emil Fischer established uric acid and a number of its derivatives as having the elementary skeleton of what he called "pure uric acid," abbreviated to purine. Out of Adolf Baeyer's work on barbituric acid came the knowledge of pyrimidine and its derivatives.

From these findings, together with what Oswald Schmiedeberg (1838-1921) had established concerning the presence of four phosphate groups in the molecule (1899), Robert Feulgen (1884-1955) constructed the following scheme of a nucleic acid. Feulgen's formula of 1918 is:

Phosphoric acid--Carbohydrate--Guanine
Phosphoric acid--Carbohydrate--Cytosine
Phosphoric acid--Carbohydrate--Thymine
Phosphoric acid--Carbohydrate--Adenine

Of the four basic components on the right, thymine occurs in the nucleic acid from the thymus gland. Yeast contains uracil instead. The difference between these two bases is one methyl group: thymine is a 5-methyluracil. In all of these basic substances, the structure of urea

NH_{2}
/
C=O
\
NH_{2}

is involved, and they form pairs of oxidized and reduced states:

PURINE PYRIMIDINE

(reduced) Adenine + (oxidized) Thymine
(oxidized) Guanine + (reduced) Cytosine

3N = CH4
| |
2H--C CH5
|| ||
1N--CH6

Pyrimidine

1N==CH6
| | H
| | 7/ N==C--NH_{2}
2H--C C--N | |
|| ||5 \ H--C C--NH
|| || \ || || \
|| || CH8 || || CH
|| || // || || //
3N--C--N N--C--N
4 9
Adenine
Purine

HN--C=O
| |
NH_{2}--C C--NH N==C--NH_{2} H--N--C=O
|| || \ | | | |
|| || CH O=C C--H O=C CH
|| || // | || | ||
N--C--N H--N--CH HN--CH

Guanine Cytosine Uracil

The carbohydrate is ribose or deoxyribose.

CHO CHO
| |
H--C--OH HO--C--H
| |
HO--C--H HO--C--H
| |
HO--C--H HO--C--H
| |
CH_{2}OH CH_{2}OH

Arabinose L-Ribose

Fischer and Piloty, 1891

H
\(1)/-----O-----\(4) (5)
C CH--CH_{2}OH
/ \(2) (3)/
HO CH_{2}--HC(OH)

Deoxyribose

The exact position of phosphoric acid was established after long work and verified by synthesis.[33]

A compound of adenine, ribose, and phosphoric acid was found in yeast, blood, and in skeletal muscle of mammals. From 100 grams of such muscle, 0.35-0.40 grams of this compound were isolated. If the muscle is at rest, the compound contains three molecules of phosphoric acid, linked through oxygen atoms. It was named adenosine triphosphate or adenyltriphosphoric acid,[34] usually abbreviated by the symbol ATP. It releases one phosphoric acid group very easily and goes over in the diphosphate, ADP, but it can also lose 2 P-groups as pyrophosphoric acid and leave the monophosphate, AMP.

N==C--NH_{2}
| |
HC C--N +----O----+
|| || \\ | |
|| || CH | OH OH | H OH
|| || / | | | | | /
N--C--N-----C--C---C--C--C--O--P=O
| | | | | \
H H H H H OH
\---------/\---------------/\--------/
Adenine D-Ribose Phosphoric
acid

This change of ATP was considered to be the main source of energy in muscle contraction by Otto Meyerhof.[35] The corresponding derivatives of guanine, cytosine, and uracil were also found, and they are active in the temporary transfer of phosphoric acid groups in biological processes.

Thus, the study of organic phosphates progressed from the comparatively simple esters connected with fatty substances of organisms to the proteins and the nuclear substances of the cell. The proportional amount of phosphorus in the former was larger than in the latter; the actual importance and function in the life of organisms, however, is not measured by the quantity but determined by the special nature of the compounds.

The study of this function is the newest phase in the history of phosphorus and represents the culmination of the previous efforts. This newest phase developed out of an accidental discovery concerning one of the oldest organic-chemical industries, the production of alcohol by the fermentative action of yeast on sugar. A transition of carbohydrates through phosphate compounds to the end products of the fermentation process was found, and it gradually proved to be a kind of model for a host of biological processes.

Specific phosphates were thus found to be indispensable for life. In reverse, the wrong kind of phosphates can destroy life. As a result, an important part of the new phase in phosphorus history consisted in the study--and use--of antibiotic phosphorus compounds.

Phosphates in Biological Processes

The first indication that phosphorus is important for life came from the experience that plants take it up from the substances in the soil. They incorporate it in their body substance. What makes phosphorus so important that they cannot grow without it? The next insight was that animals acquire it from their plant food. It is then found in bones, in fat and nerve tissue, in all cells and particularly in the cell nuclei. What are its functions there?

The answers to such questions were developed from the study of a long-known process, the conversion of carbohydrates into carbon dioxide and alcohol by yeast. It started with Eduard Buchner's discovery of 1890, that fermentation is produced by a preparation from yeast in which all living cells have been removed. When yeast is dead-ground and pressed out, the juice still has the ability to produce fermentation.

It is strange, but in many ways characteristic for the process of science, that the "riddle" of phosphorus in life was solved by first eliminating life. In such "lifeless" fermentations, Arthur Harden found that the conversion of sugar begins with the formation of a hexose phosphate (1904). The "ferment" of yeast, called zymase, proved to be a composite of several enzymes. Hans von Euler-Chelpin isolated one part of zymase, which remains active even after heating its solution to the boiling point. From 1 kilogram of yeast, he obtained 20 milligrams of this heat-stable enzyme, which he called cozymase and identified as a nucleotide composed of a purine, a sugar, and phosphoric acid.[36] In the years between the two World Wars, zymase was further resolved into more enzymes, one of them the coenzyme I, which was shown to be ADP connected with another molecule of ribose attached to the amide of nicotinic acid, or diphosphopyridine nucleotide:

^ NH_{2}
/ \\ |
/ \\ N ^
|| |-CONH_{2} //\ / \\
|| | | || N
\ // | || |
N_{+} N--+ |
| | \//
| | N
H--C------+ H--C------+
| | | |
H--C--OH | H--C--OH |
| O | O
H--C--OH | H--C--OH |
| | | |
H--C------+ O O H--C------+
| || || |
CH_{2}--O--P--O--P--O--CH_{2}
| |
O- OH

Coenzyme I

Its function is connected with the transfer of hydrogen between intermediates formed through phosphate-transferring enzymes. Fermentation proceeds by a cascade of processes, in which phosphate groups swing back and forth, and equilibria between ATP with ADP play a major role.

Many of the enzymes are closely related to vitamins. Thus, cocarboxylase A, which takes part in the separation of carbon dioxide from an intermediate fermentation product, is the phosphate of vitamin B_{1}. Others of the B vitamins contain phosphate groups, for example those of the B_{2} and B_{6} group, and in B_{12}, one lonely phosphate forms a bridge in the large molecule that contains one atom of cobalt: C_{63}H_{90}N_{14}O_{14}PCo. The formation of vitamin A from carotine occurs under the influence of ATP.

The first stages in fermentation are like those in respiration, which ends with carbon dioxide and water. These two are the materials for the reverse process in photosynthesis. When light is absorbed by the chlorophyll of green plants, one of the initial reactions is a transfer of hydrogen from water to a triphosphopyridine nucleotide, which later acts to reduce the carbon dioxide. Under the influence of ATP, phosphoglyceric acid is synthesized and further built up by way of carbohydrate phosphates to hexose sugars and finally to starch. In many starchy fruits, a small proportion of phosphate remains attached to the end product.

The synthesis of proteins is under the control of deoxyribonucleic acid or ribonucleic acid, abbreviated by the symbols DNA and RNA. The genes in the nucleus are parts of a giant DNA molecule. RNA is a universal constituent of all living cells. Where protein synthesis is intense, the content in RNA is high. Thus, the spinning glands of silkworms are extraordinarily rich in RNA.[37]

In his research on the radioactive isotope P^32, George de Hevesy gained some insight into the surprising mobility of phosphates in organisms: "A phosphate radical taken up with the food may first participate in the phosphorylation of glucose in the intestinal mucose, soon afterwards pass into the circulation as free phosphate, enter a red corpuscle, become incorporated with an adenosine triphosphoric-acid molecule, participate in a glycolytic process going on in the corpuscle, return to circulation, penetrate into the liver cells, participate in the formation of a phosphatide molecule, after a short interval enter the circulation in this form, penetrate into the spleen, and leave this organ after some time as a constituent of a lymphocyte. We may meet the phosphate radical again as a constituent of the plasma, from which it may find its way into the skeleton."[38] Much has been added in the last 30 years to complete this picture in many details and to extend it to other biochemical processes, including even the changes of the pigments in the retina in the visual process, or in the conversion of chemical energy to light by bacteria and insects.

Medicines and Poisons

In the delicate balance of these processes, disturbances may occur which can be remedied by specific phosphate-containing medicines. Thus, adenosine phosphate has been recommended in cases of angina pectoris and marketed under trade names like sarkolyt, or in compounds named angiolysine. A considerable number of physiologically active organic phosphates can be found in the patent literature.[39] Yeast itself is considered to be a valuable food additive.

On the other hand, there are phosphate compounds that act as poisons. One group of such compounds was discovered in 1929 by W. Lange, who wrote: "Of interest is the strong action of mono-fluorophosphate esters on the human body--the effect is produced by very small quantities."[40] Diisopropyl fluorophosphate has since become a potential agent for chemical warfare. It inactivates an enzyme which controls the transmission of nerve impulses to muscle, acetylcholine esterase.

Organic esters of phosphoric acids are used as insecticides. The hexa-ethylester of tetraphosphoric acid, prepared by Gerhard Schrader by heating triethylphosphate with phosphorus oxychloride,[41] actually contains tetraethylpyrophosphate (TEPP) among others. Bayer's Dipterex, the dimethyl ester of 2,2,2-trichloro-1-hydroxyethyl-phosphonate, has been modified to dimethyl-2,2-dichlorovinyl-phosphate and is especially active against the oriental fruit fly.[42]

Cl H O
| | || OCH_{3}
| | ||/
Cl--C--C--P Bayer's L 13/59
| | \ (Dipterex)
| | OCH_{3}
Cl OH

(CH_{3})_{2}N O O N(CH_{3})_{2}
\|| ||/
P--O--P Schradan
/ \
(CH_{3})_{2}N N(CH_{3})_{2}

Octamethylpyrophosphoramide

The story of phosphorus, which began 300 years ago, has acquired new importance in this century. Many scientists have contributed to it: 13 of them have received Nobel Prizes for work directly bearing on the chemical and biological importance of phosphorus compounds. In chronological order, they are: Eduard Buchner, Albrecht Kossel, Otto Meyerhof, Arthur Harden, Hans von Euler-Chelpin, George de Hevesy, Carl F. Cori, Gerty T. Cori, Fritz Lipmann, Lord Alexander Todd, Arthur Kornberg, Severo Ochoa, and Melvin Calvin. The developers of industrial production and commercial utilization of phosphate compounds have had other rewards.

Some impression of the continuing growth in this field[43] can be gained from the following data.

PHOSPHATE ROCK

annually "sold or used by producer" in the United States in million long tons (2,240 lbs.)

1880 0.2
1890 0.5
1900 1.5
1910 2.655
1920 4.104
1930 3.926
1940 4.003
1945 5.807
1950 11.114
1955 12.265
1955 (world: about 56)
1960 17.202
1962 19.060

Sources: U.S. Bureau of the Census. _Historical Statistics of the United States 1789-1945_ (1949); _Statistical Abstract of the United States._

ELEMENTAL PHOSPHORUS

annually produced in the United States in short tons (2,000 lbs.)

1939 43,000
1944 85,679
1950 153,233
1956 312,200
1958 335,750
1959 366,350
1960 409,096
1961 430,617
1962 451,970

Source: U.S. Department of Commerce.

* * * * *

FOOTNOTES

[1] WILHELM HOMBERG, _Mémoires Académie, 1666-1699_ (Paris, 1730),
vol. 10, under date of April 30, 1692, pp. 57-61.

[2] FORTUNIO LICETUS, _Lithiophosphorus sive de lapide Bononiensi_
(Venice, 1640).

[3] Cited in PETER JOSEPH MACQUER _Chymisches Wörterbuch_, 2nd ed.
(Leipzig: Weidmann, 1789), vol. 4, p. 508, footnote "c" as
"Kletwich (de phosph. liqu. et solid. 1689, Thes. II)."

[4] FERDINAND HOEFER, _Histoire de la Chimie_ (Paris, 1843), vol. 1,
p. 339.

[5] G. W. VON LEIBNIZ, _Mémoires Académie_ (Paris, 1682); _Akademie
der Wissenschaften, Miscellanea Berolinensia_ (Berlin, 1710),
vol. 1, p. 91.

[6] JEAN HELLOT, _Mémoires Académie 1737_ (Paris, 1766), under date
of November 13, 1737, pp. 342-378.

[7] MACQUER, op. cit. (footnote 3), p. 551.

[8] A. S. MARGGRAF, _Akademie der Wissenschaften, Miscellanea
Berolinensia_ (Berlin, 1743), vol. 7, 342 ff.; see also WILHELM
OSTWALD _Klassiker der Exakten Naturwissenschaften_ (Leipzig:
Engelmann, 1913), no. 187.

[9] G. HANCKEWITZ, [Hankwitz], _Philosophical Transactions of the
Royal Society of London_, 1724-1734, abridged (London, 1809),
vol. 7, pp. 596-602.

[10] ANTOINE LAURENT LAVOISIER, "Sur la Combustion du Phosphore de
Kunckel, Et sur la nature de l'acide qui resulte de cette
Combustion," _Mémoires Académie 1777_, (Paris, 1780), pp. 65-78.

[11] GUYTON DE MORVEAU and others, _Méthode de Nomenclature Chimique_,
Proposée par MM. de Morveau, Lavoisier, Bertholet, & de Fourcroy
(Paris, 1787), plate 9.

[12] MACQUER, op. cit. (footnote 3), p. 513.

[13] MARIE BOAS, _Robert Boyle and Seventeenth Century Chemistry_ (New
York: Cambridge University Press, 1958), p. 226; see also
WYNDHAM MILES, "The History of Dr. Brand's Phosphorus
Elementarus," _Armed Forces Chemical Journal_ (November-December
1958), p. 25.

[14] ARCHIBALD CLOW and NAN L. CLOW, _The Chemical Revolution_
(London: Batchworth Press, 1952), p. 451.

[15] ÉMILE KOPP, _Comptes-rendus hebdomadaires des Séances de
l'Académie des Sciences, Paris_ (1844), vol. 18, p. 871; WILHELM
HITTORF, _Annalen der Chemie und Pharmazie_, suppl. to vol. 4,
p. 37; ANTON SCHRÖTTER, _Annales de Chimie et de Physique_,
series 3, vol. 24 (1848), p. 406; see also Schrötter's report on
"Phosphor und Zündwaaren" in A. W. VON HOFMANN, _Bericht über
die Entwicklung der Chemischen Industrie_ (Braunschweig: Vieweg,
1875), pp. 219-246.

[16] R. GLAUBER, _Furni Novi Philosphici_ (Amsterdam, 1649), vol. 2,
pp. 12 ff.

[17] HERMANN SCHELENZ, _Geschichte der Pharmazie_ (Berlin: Springer,
1904), p. 598.

[18] J. PERSONNE, _Comptes-rendus ..._, Paris (1869), vol. 68, pp.
543-546.

[19] A. WURTZ, _Dictionnaire de Chimie_ (Paris, 1876), vol. 2, part 2,
p. 951.

[20] KARL W. SCHEELE, _Nachgelassene Briefe und Aufzeichnungen_, edit.
A. E. Nordenskiöld (Stockholm: Norstedt, 1892), pp. 38, 144.

[21] J. J. BERZELIUS, _Lehrbuch_, transl. F. Wöhler (Dresden, 1827),
vol. 3, part 1, p. 96.

[22] THOMAS GRAHAM, _Philosophical Transactions of the Royal Society
of London_ (1833), pp. 253-284.

[23] JUSTUS LIEBIG'S _Annalen der Pharmacie_ (1838), vol. 26,
p. 113 ff.

[24] A. WURTZ, _Annales de Chimie et de Physique_, series 3, vol. 16
(1846), p. 190.

[25] CARROLL D. WRIGHT, _The Phosphate Industry in the United States_,
sixth special report of the Commissioner of Labor (Washington,
1893).

[26] J. STOKLASA, _Biochemischer Kreislauf des Phosphat-Ions im Boden,
Centralblatt für Bakteriologie ..._ (Jena: Fischer, March 22,
1911), vol. 29, nos. 15-19.

[27] N. T. GOBLEY, _Comptes-rendus_ ..., Paris (1845), vol. 21,
p. 718.

[28] A. WURTZ, _Comptes-rendus_ ..., Paris (1868), vol. 66, p. 772.

[29] L. THUDICHUM, _Die chemische Constitution des Gehirns des
Menschen und der Tiere_ (1901); see also H. WITTCOFF, THE
PHOSPHATIDES (New York: Reinhold, 1951).

[30] WILLIAM CROOKES, _British Association for the Advancement of
Science, Reports_ (1887), sec. B, p. 573.

[31] J. E. COURTOIS and A. LINO, _Progress in the Chemistry of Organic
Natural Products_, edit. L. Zechmeister (Vienna: Springer
Verlag, 1961), vol. 19, p. 316-373.

[32] A. WURT, _Dictionnaire de Chimie_, supp. part 2, [n.d.] p. 1087;
A. KOSSEL, _Zeitschrift für physiologische Chemie_, series 3
(1879), p. 284.

[33] ALEXANDER TODD, _Les Prix Nobel en 1957_ (Stockholm).

[34] HANS VON EULER-CHELPIN, _Les Prix Nobel en 1929_ (Stockholm).

[35] O. MEYERHOF and E. LUNDSGAARD, _Naturwissenschaften_ (Berlin,
1930), vol. 18, pp. 330, 787.

[36] K. LOHMANN, _Naturwissenschaften_ (Berlin, 1929), vol. 17, p.
624; C. H. FISKE and Y. SUBBAROW, _Science_ (Washington, 1929),
vol. 70, p. 381 f.

[37] J. BRACHET, _Scientia, Revista di Scienza_ (1960), vol. 95, p.
119.

[38] GEORGE DE HEVESY, _Les Prix Nobel en 1940_ (Stockholm). See also
EDUARD FARBER, _Nobel Prize Winners in Chemistry_, 2nd ed. (New
York: Schuman, 1963), p. 179.

[39] See, e.g., _Chemical Week_, vol. 77 (September 3, 1955), p. 79
f.; J. BOLLE, _Chimie et Industrie_ (1960), vol. 83, p. 252.

[40] W. LANGE, _Berichte der Deutschen Chemischen Gesellschaft_
(Berlin, 1929), vol. 62, p. 793; vol. 65 (1932), p. 1598.

[41] GERHARD SCHRADER, U.S. patent 2,336,302 of 1943 (priority in
Germany, 1938); S. A. HALL and M. JACOBSON, _Industrial and
Engineering Chemistry_ (1943), vol. 40, p. 694.

[42] A. M. MATTSEN and others, _Journal of Agriculture and Food
Chemistry_ (1955), vol. 3, p. 319.

[43] JOHN B. VAN WAZER, _Phosphorus and its Compounds_, 2 vols. (vol.
1, _Chemistry_; vol. 2 _Technology, Biological Functions and
Applications_, New York: Interscience, 1958, 1961.

* * * * *

Paper 40 - Transcriber's Note

The following typographical errors have been corrected:

Page 180 "Abfällen, Vieweg, Braunschweig," - had "Viewig".

Page 188 "wires d from the dynamo D" - had "dynano".

Page 192 "But phosphatides occur" - had "phosphatide soccur".

Page 193 "the nucleic acid from the thymus" - had "nucleidic".

Page 199 "acetylcholine esterase." - had "acetylcholin".

Page 200 "George de Hevesy, Carl F. Cori," - comma added after Hevesy.

Footnote 39: "See, e.g., Chemical Week, vol. 77" - had "See. e.g."

The spelling of "Bertholet" [Claude Louis Berthollet] is as given on the original title page of the work referenced in this paper.

Inconsistent hyphenation of chemical names has been retained.

* * * * *

CONTRIBUTIONS FROM
THE MUSEUM OF HISTORY AND TECHNOLOGY.

PAPER 41

TUNNEL ENGINEERING--A MUSEUM TREATMENT

_Robert M. Vogel_