Chapter XII: TECHNOLOGY.--Gaseous Illuminants.--By Prof. VIVIAN B (4)

Mr. Thomson attempted to separate and determine the quantity of carbon monoxide and hydrocarbons present in the flue gases from various forms of gas stoves and burners, but, like every other observer who has attempted to solve this most difficult problem, he found it so beset with difficulties that he had to abandon it, and contented himself with determining the total amounts of carbon and hydrogen escaping in an unburned condition, experiments which showed that the combustion of gas in stoves for heating purposes is much more incomplete than one had been in the habit of supposing, but his experiments give no clew as to whether the incompletely burned matter consisted of such deleterious gases as carbon monoxide and acetylene, or comparatively harmless gases, such as marsh gas and hydrogen. After considerable work upon the subject, I have succeeded in doing this by a very delicate process of analysis, and I now wish to lay some of my results before you.

If a cold substance, metal or non-metal, be placed in a flame, whether it be luminous or non-luminous, it will be observed that there is a clear space, in which no combustion is taking place, formed round the cool surface, and that as the body gets heated so this space gets less and less until, when the substance is at the same temperature as the flame itself, there is contact between the two. Moreover, when a luminous flame is employed in this experiment the space still exists between the cool body and the flame, but you also notice that the luminosity is decreased over a still larger area although the flame exists.

This meaning that, in immediate contact with the cold body, the temperature is so reduced that the flame cannot exist, and so is extinguished over a small area; while over a still larger space the temperature is so reduced that it is not hot enough to bring about decomposition of the heavy hydrocarbons with liberation of carbon to the same extent as in hotter portions of the flame. Now, inasmuch as when water is heated or boiled in an open vessel, the temperature cannot rise above 100°C., and as the temperature of an ordinary flame is over 1,000°C., it is evident that the burning gas can never be in contact with the bottom of the vessel, or, in other words, the gas is put out before combustion is completed, and the unburned gas and products of incomplete combustion find their way into the air and render it perfectly unfit for respiration.

The portion of the flame which is supposed to be the hottest is about half an inch above the tip of the inner zone of the flame, and it is at this point that most vessels containing water to be heated are made to impinge on the flame; and it is this portion of the flame, also, which is utilized for raising various solids to a temperature at which they radiate heat.

In order to gain an insight into the amount of contamination which the air undergoes when a geyser or cooking stove is at work, I have determined the composition of the products of combustion, and the unburned gases escaping when a vessel containing water at the ordinary temperatures is heated up to the boiling point by a gas flame, the vessel being placed, in the first case, half an inch above the inner cone of the flame, and in the second, at the extreme outer tip of the flame.

GASES ESCAPING DURING CHECKED COMBUSTION.

| Bunsen flame. | Luminous flame. +-----------+-----------+-------------+---------- | Inner. | Outer. | Inner. | Outer. +-----------+-----------+-------------+---------- Nitrogen | 75.75 | 79.17 | 77.52 | 69.41 Water vapor | 13.47 | 14.29 | 11.80 | 19.24 Carbon dioxide | 2.99 | 5.13 | 4.93 | 8.38 Carbon monoxide | 3.69 | Nil. | 2.45 | 2.58 Marsh gas | 0.51 | 0.31 | 0.95 | 0.39 Acetylene | 0.04 | Nil. | 0.27 | Nil. Hydrogen | 3.55 | 0.47 | 2.08 | Nil. +-----------+-----------+-------------+---------- | 100.00 | 100.00 | 100.00 | 100.00

These figures are of the greatest interest, as they show conclusively that the extreme top of the Bunsen flame is the only portion of the flame which can be used for heating a solid substance without liberating deleterious gases; and this corroborates the previous experiment on the gases in the outer zone of a flame, which showed that the outer zone of a Bunsen flame is the only place where complete combustion is approached.

Moreover, this sets at rest a question which has been over and over again under discussion, and that is whether it is better to use a luminous or a non-luminous flame for heating purposes. Using a luminous flame, it is impossible to prevent a deposit of carbon, which is kept by the flame at a red heat on its outer surface, and the carbon dioxide formed by the complete combustion of the carbon already burned up in flame is reduced by this back to carbon monoxide, so that even in the extreme tip of a luminous flame it is impossible to heat a cool body without giving rise to carbon monoxide, although acetylene being absent, gas stoves, in which small flat flame burners are used, have not that subtile and penetrating odor which marks the ordinary atmospheric burner stove, with the combustion checked just at the right spot for the formation of the greatest volume of noxious products.

It is the contact of the body to be heated with the flame before combustion is complete which gives rise to the greatest mischief; any cooling of the flame extinguishes a portion of the flame, and the gases present in the flame at the moment of extinction creep along the cooled surface and escape combustion.

Dr. Blochmann has shown the composition of the gases in various parts of the Bunsen flame to be as follows:

Height above tube. |In tube. |1 inch. |2 inch. |3 inch. |Complete
| | | | |combustion
-------------------------------------------------------------------
Air with 100 vols. | | | | |
gas | 253.9 | 284.7 | 284.5 | 484.3 | 608.8
Hydrogen | 48.6 | 36.4 | 17.7 | 16.1 | Nil.
Marsh gas | 39.0 | 40.1 | 28.0 | 5.7 | Nil.
Carbon monoxide | 2.9 | 2.2 | 19.9 | 12.7 | Nil.
Olefiant gas | 4.0 | 3.4 | 2.2 | Nil. | Nil.
Buteylene | 3.0 | 2.5 | 1.6 | Nil. | Nil.
Oxygen | 52.7 | 52.0 | 21.7 | Nil. | Nil.
Nitrogen | 199.1 | 223.8 | 225.9 | 382.4 | 482.3
Carbon dioxide | 0.8 | 3.5 | 13.0 | 41.7 | 62.4
Water vapor | 3.1 | 11.8 | 45.8 | 116.1 | 141.2
-------------------------------------------------------------------

Which results show that it would be impossible to check the flame anywhere short of the extreme tip (where complete combustion is approximately taking place), without liberating deleterious products. I think I have said enough to show that no gas stove, geyser or gas cooking stove should be used without ample and thorough means of ventilation being provided, and no trace of the products of combustion should be allowed to escape into the air; until this is done, the use of improper forms of stoves will continue to inflict serious injury on the health of the people using them, and this will gradually result in the abandonment of gas as a fuel, instead of, as should be the case, its coming into general use. The English householder is far too prone to accept what is offered to him, without using his own common sense, and will buy the article which tickles his eye the most and his pocket the least, on the bare assurance of the shopkeeper, who is only anxious to sell; but when he finds that health and comfort are in jeopardy, and has discarded the gas stove, it will take years of labor to convince him that it was the misuse of gas which caused the trouble. Already signs are not wanting that the employers of gas stoves are beginning to fight shy of them, and I earnestly hope that the gas managers of the kingdom will bring pressure to bear upon the stove manufacturers to give proper attention to this all important question.

So strongly do I feel the importance of this question to the gas world and the public, that I freely offer to analyze the products of combustion given off by any gas stove or water heater sent to me at Greenwich during the next six months, on one condition, and that is that the results, good, bad, or indifferent, will be published in a paper before this Society, which has always been in the front when matters of great sanitary importance to the public had to be taken up. And if after that the public like to buy forms of apparatus which have not been certified, it is their own fault; but I do think that the maker of any stove or geyser which causes a death should be put upon his trial for manslaughter.

In conclusion, let us consider for a moment what is likely to be the future of gas during the next half century. The labor troubles, bad as they are and have been, will not cease for many a weary year. The victims of imperfect education (more dangerous than none at all, as, while destroying natural instinct, it leaves nothing in its place) will still listen and be led by the baneful influence of irresponsible demagogues, who care for naught so long as they can read their own inflammatory utterances in the local press, and gain a temporary notoriety at the expense of the poor fools whose cause they profess to serve. The natural tendency of this will be that every labor-saving contrivance that can will be pressed into the gas manager's service; and that, although coal (of a poorer class than at present used) will still be employed as a source of gas, the present retort setting will quickly give way to inclined retorts on the Coze principle; while, instead of the present wasteful method of quenching the red hot coke, it will be shot direct into the generator of the water gas plant, and the water gas carbureted with the benzene hydrocarbons derived from the smoke of the blast furnace and coke oven, or from the creosote oil of the tar distiller, by the process foreshadowed in the concluding sentences of my last lecture. It will then be mixed with the gas from the retorts, and will supply a far higher illuminant than we at present possess. In parts of the United Kingdom, such as South Wales, where gas coal is dear, and anthracite and bastard coals are cheap, water gas highly carbureted will entirely supplant coal gas, with a saving of fifty per cent. on the prices now existing in those districts. While these changes have been going on, and while improved methods of manufacture have been tending to the cheapening of gas, it will have been steadily growing in public favor as a fuel; and if in years to come the generation of electricity should have been so cheapened as to allow it to successfully compete with gas as an illuminant, the gas works will still be found as busy as of yore, the holder of gas shares as contented as to-day; for with a desire for a purer atmosphere and a white mist instead of a yellow fog, gas will have largely supplanted coal as a fuel, and gas stoves, properly ventilated and free from the reproaches I have hurled at them to-night, will burn a gas far higher in its heating power, far better in its power of bearing illuminating hydrocarbons, and free from poisonous constituents.

When the demand for it arises, hydrogen gas can be made as cheaply as water gas itself, and when time is ripe for a fuel gas for use in the house, it is hydrogen and not water gas which will form its basis. With carbureted water gas and 20 per cent. of carbon monoxide we are still below the limit of danger, but a pure water gas with over 40 per cent. of the same insidious element of danger will never be tolerated in our households. Already a patent has been taken by Messrs. Crookes and Ricarde-Seaver for purifying water gas from carbon monoxide, and converting it mainly into hydrogen by passing it at a high temperature through a mixture of lime and soda lime, a process which is chemically perfect, as the most expensive portion of the material used could be recovered; but in the present state of the labor market it is not practical, as for the making of every 100,000 cubic feet of gas, fifteen tons of material would have to be handled, the cost of labor alone being sufficient to prevent its being adopted; moreover, hydrogen can be made far cheaper directly.

From the earliest days of gas making, the manufacture of hydrogen by the passage of steam over red-hot iron has been over and over again mooted, and attempted on a large scale, but several factors have combined to render it futile.

In the first place, for every 478.5 cubic feet of hydrogen made under perfect theoretical conditions never likely to be obtained in practice, 56 lb. of iron were converted into the magnetic oxide, and as there was no ready sale for this article, this alone would prevent its being used as a cheap source of hydrogen; the next point was that when steam was passed over the red-hot iron, the temperature was so rapidly lowered that the generation of gas could only go on for a very short period, while, finally, the swelling of the mass in the retort and fusion of some of the magnetic oxide into the side renders the removal of the spent material almost an impossibility. These difficulties can, however, be got over. Take a fire clay retort, six feet long and a foot in diameter, and cap it with a casting bearing two outlet tubes closed by screw valves, while a similar tube leads from the bottom of the retort. Inclose this retort by a furnace chamber of iron lined with fire brick, leaving a space of two feet six inches round the retort, and connect the top of the furnace chamber with one opening at the top of the upright retort, while air blasts lead into the bottom of the furnace chamber, below rocking fire bars, which start at bottom of the retort, and slope upward, to leave room for ash holes closed by gas tight covers. The retort is filled with iron or steel borings, alone if pure hydrogen is required, or cast into balls with pitch if a little carbon monoxide is not a drawback, as in foundry work. The furnace chamber is now filled with coke, fed in through manholes, or hoppers, in the top, and the fuel being ignited, the blast is turned on, and the mixture of nitrogen and carbon monoxide passes over the iron, heating it to a red heat, while the fuel in contact with the retort does the same thing.

When the fuel and retort full of iron are at a cherry-red heat, the air blast is cut off, and the pipe connecting the furnace and retort, together with the pipe in connection with the bottom of the retort, are closed, and steam, superheated by passing through a pipe led round the retort or interior wall of the furnace, is injected at the bottom of the red-hot mass of iron, which decomposes it, forming magnetic oxide of iron and hydrogen, which escapes by the second tube at the top of the retort, and is led away either to a carbureting chamber if required for illumination, or direct to the gasholder if wanted as a fuel. The mass of incandescent fuel in the furnace chamber, surrounding the retort, keeping up the temperature of retort and iron sufficiently long to enable the decomposition to be completed.

The hydrogen and steam valves are now closed and the air blast turned on. The hot carbon monoxide passing over the hot magnetic oxide quickly reduces it down to metallic iron, which, being in a spongy condition, acts more freely on the steam during later makes than it did at first, and being infusible at the temperature employed, may be used for a practically unlimited period.

What more simple method than this could be desired? Here we have the formation of the most valuable of all fuel gases at the cost of the coke and steam used, a gas also which has double the carrying power for hydrocarbon vapors possessed by coal gas, while its combustion gives rise to nothing but water vapor.

In this course of lectures I have left much unsaid and undone which I should have liked to have had time to accomplish, and if I have been obliged to leave out of consideration many important points, it is the time at my disposal and not my will which is to blame. And now, in conclusion, I wish to express my thanks to my assistants, Messrs. J.A. Foster and J.B. Warden, who have heartily co-operated with me in much of the work embodied in these lectures.

* * * * *

STEREOSCOPIC PROJECTIONS.

The celebrated philosopher Bacon, the founder of the experimental method, claimed that we see better with one eye than with two, because the attention is more concentrated and becomes profounder. "On looking in a mirror," says he, "we may observe that, if we shut one eye, the pupil of the other dilates." To this question: "But why, then, have we two eyes?" he responds: "In order that one may remain if the other gets injured." Despite the reasoning of the learned philosopher, we may be permitted to believe that the reason that we have two eyes is for seeing better and especially for perceiving the effects of perspective and the relief of objects. We have no intention of setting forth here the theory of binocular vision; one simple experiment will permit any one to see that the real place of an object is poorly estimated with one eye. Seated before a desk, pen in hand, suddenly close one eye, and, at the same time, stretch out the arm in order to dip the pen in the inkstand; you will fail nine times out of ten. It is not in one day that the effects of binocular vision have been established, for the ancients made many observations on the subject. It was in 1593 that the celebrated Italian physicist Porta was the first to give an accurate figure of two images seen by each eye separately, but he desired no apparatus that permitted of reconstituting the relief on looking at them. Those savants who, after him, occupied themselves with the question, treated it no further than from a theoretical point of view. It was not till 1838 that the English physicist Wheatstone constructed the first stereoscopic apparatus permitting of seeing the relief on examining simultaneously with each of the eyes two different images of an object, one having the perspective that the right eye perceives, and the other that the left eye perceives.

This apparatus is described in almost all treatises on physics. We may merely recall the fact that it operated by reflection, that is to say, the two images were seen through the intermedium of two mirrors making an angle of 45 degrees. The instrument was very cumbersome and not very practical. Another English physicist, David Brewster, in 1844 devised the stereoscope that we all know; but, what is a curious thing, he could not succeed in having it constructed in England, where it was not at first appreciated. It was not till 1850 that he brought it to Paris, where it was constructed by Mr. Soleil and his son-in-law Duboscq. Abbot Moigno and the two celebrated opticians succeeded, not without some difficulty, in having it examined by the _official_ savants; but, at the great exposition of 1851, it was remarked by the Queen of England, and from this moment Messrs. Soleil & Duboscq succeeded with difficulty only in satisfying the numerous orders that came from all parts. As photography permitted of easily making identical images, but with different perspective, it contributed greatly to the dissemination of the apparatus.

The stereoscope, such as we know it, presents the inconvenience of being incapable of being used by but one person at once. Several inventors have endeavored to render the stereoscopic images visible to several spectators at the same time. In 1858, Mr. Claudet conceived the idea of projecting the two stereoscopic images upon ground glass in superposing them. The relief was seen, it appears, but we cannot very well explain why; the idea, however, had no outcome, because the image, being quite small, could be observed by but three or four persons at once. It was Mr. D'Almeida, a French physicist, who toward the same epoch solved the problem in a most admirable manner, and we cannot explain why his process (that required no special apparatus) fell into the desuetude from which Mr. Molteni has just rescued it and obtained much success.

This is in what it consists: The impression of the relief appears when each eye sees that one of the two images which presents the perspective that it would perceive if it saw the real object. If we take two transparent stereoscopic images and place each of them in a projection lantern, in such a way that they can be superposed upon the screen, we shall obtain thereby a single image. It will always be a little light and soft, as the superposition cannot be effected accurately, the perspective not being the same for each of them. It is a question now to make each eye see the one of the two images proper to it. To this effect, Mr. D'Almeida conceived the very ingenious idea of placing green glass in the lantern in front of the image having the perspective of the right eye, and a red glass in front of the other image. As green and red are complementary colors, the result was not changed upon the screen; there was a little less light, that was all. But if, at this moment, the spectator places a green glass before his right eye and a red one before his left, he will find himself in the condition desired for realizing the effect sought.

Each eye will then see only the image responding to the coloration chosen, and, as it is precisely the one which has the perspective proper to it, the relief appears immediately. The effect is striking. We perceive a diffused image upon the screen with the naked eye, but as soon as we use one special eye-glass the relief appears with as much distinctness as in the best stereoscope. One must not, for example, reverse his eye-glass, for if (things being arranged as we have said) he looks through a red glass before his right eye, and through a green one before his left, it is the image carrying the perspective designed for the right eye that will be seen by the left eye, and reciprocally. There is then produced, especially with certain images, a very curious effect of reversed perspective, the background coming to the front.

Now that photography is within every one's reach, and that many amateurs are making stereopticon views and own projection lanterns, we are persuaded that the experiment will be much more successful than it formerly was. An assemblage of persons all provided with colored eye-glasses is quite curious to contemplate. Our engraving represents a stereopticon seance, and the draughtsman has well rendered the effect of the two luminous and differently colored fascicles superposed upon the screen.

In a preceding note upon the same subject, Mr. Hospitalier remarked that upon combining these effects of perspective with those of the praxinoscope, which give the sensation of motion, we would obtain entirely new effects. It would be perhaps complicated as to the installation, and especially as to the making of the images, but, in certain special cases (for giving the effect of a machine in motion, for example), it might render genuine services.--_La Nature_.

* * * * *

THE EFFECT ON FOWLS OF NITROGENOUS AND CARBONACEOUS RATIONS.[1]

[Footnote 1: This article is condensed by permission from a thesis prepared for the degree of Bachelor of Science in Agriculture, by James Edward Rice, a graduate of the class of 1890. The work was planned and wholly carried out in the most careful manner by Mr. Rice under the immediate supervision of the Director. The results have been thought worthy of publication in the _Cornell Station Bulletin_.]

On July 2, 1889, ten Plymouth Rock hens, one year old, and as nearly as possible of uniform size, were selected from a flock of thirty-five. At the same time ten chickens, hatched from the same hens mated with a Plymouth Rock cock, were similarly chosen. The chickens were about six weeks old, healthy and vigorous and of nearly the same size. Up to the time of purchase both hens and chickens had full run of the farm. The hens foraged for themselves and were given no food; the chickens had been fed corn meal dough, sour milk and table scraps.

A preliminary feeding trial was continued for twenty-five days, during which time both hens and chickens were confined, all together, in a fairly well lighted and ventilated room, and fed a great variety of food, in order that all should go into the feeding trial as nearly as possible in the same condition. During this preliminary feeding both hens and chickens increased in live weight. The ten hens from a total of 44 lb. 12 oz. to 47 lb. 1.5 oz., or 3.75 oz. each, and laid 93 eggs. The chickens from a total of 9 lb. 15 oz. to 18 lb., or 12.9 oz. each.

Food, shells and water were kept constantly before the fowls. Basins which contained the food and water were kept within a box constructed of lath, so arranged that the fowls could reach between the slats and procure food and drink without wasting or soiling.

July 26th the hens and chickens were each separated into two lots of five each, as follows:

Hens, nitrogenous ration, weighed 23 lb. 8.5 oz.
Hens, carbonaceous ration, weighed 23 lb. 9 oz.
Chickens, nitrogenous ration, weighed 8 lb. 15 oz.
Chickens, carbonaceous ration, weighed 9 lb. 1 oz.

The four lots were placed in separate pens where they remained during the entire experiment, which lasted 125 days. They were fed and watered once daily, and an account kept of the food eaten and water drank. At each feeding the food and water remaining were weighed back and deducted from the amount charged at the previous feeding.

The hens and chickens fed a nitrogenous ration were given daily all they would eat of the following mixture: 1/3 part wheat bran, 1/3 part wheat shorts, 1/3 part cotton seed meal, 2 parts skimmed milk, and will be designated Lot I.

The hens and chickens fed a carbonaceous ration were given daily all they would eat of a ration of cracked maize and maize dough, and will be designated Lot II.

Both groups were given a small amount of green clover as long as it lasted, and afterward cabbage.

For convenience the experiment was divided into five periods of twenty five days.

FOOD CONSUMED AND INCREASE IN LIVE WEIGHT.

During the first period all the fowls seemed in good health except the carbonaceous fed chickens; they, during this as in all succeeding periods, were restless and peevish, always moping or hunting for something to eat, though their trough was filled. When fed they would greedily take a few mouthfuls and then, with their hunger still unappeased, would leave the dish. They always ate ravenously the green food which was given them, as did the hens and chickens of Lot I. The hens of Lot II., on the contrary, seemed quite willing to squat about the pen and subsist on the maize diet, and strangely enough cared little for green food. The clear maize diet was accompanied by such ill effects that the chickens of each lot, after the first period, were given daily each one-fourth ounce of wheat, and the hens each one ounce. The wheat was increased during the fourth and fifth periods in the case of the chickens to one ounce each. During the second period one of the chickens fed nitrogenous food, and during the third period another of the same lot were taken ill and removed from the experiment. Both seemed to be suffering from impacted crops, as the stomach and gizzard in each case were found to be empty.

The fact that the sick chickens disliked the nitrogenous ration, and since the first period the amount of food eaten by the hens and chickens of Lot I had continually decreased, led to the belief that their food might be too nitrogenous, and as during the last days of the third period one of the hens in Lot I was also ill, it was decided to discontinue the use of cotton seed meal and to use linseed meal instead. The hen recovered soon after the change in food.

The supply of skim milk running short in the last two periods, water was used instead in mixing the ration of the lots fed nitrogenous food.

At the beginning of the fifth period one-half of the linseed meal in the ration of Lot I was removed, and cotton seed meal substituted. This combination seemed a happy one, for on this ration both hens and chickens made large gains.

At the end of the experiment little difference could be seen in the hens of the two groups; but the two lots of chickens were in striking contrast. While the chickens fed on nitrogenous food were large, plump, healthy, active, and well feathered, the chickens fed on a carbonaceous ration were in general much smaller, sickly, and in several cases almost destitute of feathers. Two of them had perfectly bare backs, and so ravenous were they for flesh and blood that they began eating one another.

The inability of the chickens fed on a carbonaceous diet to throw out new feathers and the ability of the chickens fed on a nitrogenous diet to grow an enormous coat of feathers is a splendid illustration of the effect of the composition of the food in supplying certain requirements of animal growth. It was plain to see that maize, even when assisted by a small amount of wheat and green clover, could not supply sufficient nitrogen for the growth of feathers.

It will thus be seen that while both lots of hens lost weight during the experiment, the loss was slightly greater with those fed nitrogenous food, but these produced by far the most eggs.

The chickens fed on nitrogenous food just about doubled in weight, while those fed carbonaceous food only added about one-third to their weight.

PRODUCTION OF EGGS.

During the first week the carbonaceous fed hens laid three eggs while the others laid two. The two groups were, therefore, practically evenly divided at the start as to the condition of the laying stage. At the end of the first period the nitrogenous fed hens had laid forty-three eggs and the carbonaceous fed hens had laid twenty. During the next twenty-five days the former laid thirty and the latter six; during the third period the former laid six and the latter not any. From this time on no eggs were received from either group. The decline in egg production was probably due in large part to the fact that the hens began to moult during the second period, and continued to do so during the rest of the experiment.

The eggs laid by the nitrogenous fed hens were of small size, having a disagreeable flavor and smell, watery albumen, an especially small, dark colored yolk, with a tender vitelline membrane, which turned black after being kept several weeks. While the eggs of the carbonaceous fed hens were large, of fine flavor, of natural smell, large normal albumen, an especially large, rich yellow yolk, with strong vitelline membrane, which was perfectly preserved after being kept for weeks in the same brine with the other eggs.

TOTAL FOOD CONSUMED DURING EXPERIMENT. _____________________________________________________________________ Lot. I.--Nitrogenous. | Lot. II.--Carbonaceous. _________________________________|___________________________________ | | | | | | Hens. |*Chicks| | Hens. |Chicks. |_______|_______| |_______|________ | lb. | lb. | | lb. | lb. Bran. | 29.90 | 21.85 | Maize. | 82.15 | 51.30 Shorts. | 29.90 | 21.85 | Green clover. | 18.75 | 18.75 Cotton seed meal.| 21.48 | 13.24 | Cabbage. | 16.00 | 16.00 Linseed meal. | 8.43 | 8.61 | Wheat | 15.63 | 11.71 Skimmed milk. |105.49 | 61.33 | | | Wheat. | 15.63 | 11.71 | | | Green clover. | 18.75 | 18.75 | | | Cabbage. | 16.00 | 16.00 | | | _________________|_______|_______|__________________|_______|________ Total. |245.58 |173.34 | Total. |132.53 | 92.76 Nutritive ratio.| 1:3.1 | 1:3 | Nutritive ratio. | 1:7.8 | 1:8 _________________|_______|_______|__________________|_______|________

* Calculated for five chicks, based upon the amount eaten by the three after the two sick were removed.

EGGS LAID AND GAIN IN WEIGHT--HENS.
____________________________________________________________________
| |
| Lot I. | Lot II.
| Nitrogenous. | Carbonaceous.
|______________|________________
| |
Live weight, July 26. | 23.53 | 23.56
" " November 27. | 21.31 | 22.00
Loss. | 2.22 | 1.56
Number of eggs laid. | 79.00 | 26.00
Weight " " " lb. | 8.25 | 2.92
Average weight of eggs, oz. | 1.67 | 1.80
Gain in weight, including eggs, lb. | 6.03 | 1.36
____________________________________|______________|________________

GAIN IN LIVE WEIGHT--CHICKENS.
____________________________________________________________________
| |
| Lot I. | Lot II.
| Nitrogenous. | Carbonaceous.
|______________|________________
| |
Live weight, July 26. | 8.94 | 9.06
" " November 27. | 17.89 | 12.63
Gain, lb. | 8.95 | 3.57
" per cent. | 100.11 | 39.40
____________________________________|______________|________________

Samples of the eggs from each lot of fowls were privately marked and sold to a boarding house where the cook did not know that the eggs were undergoing a test. On meeting the cook several days later the following words were heard: "Do you expect me to cook such eggs as these! About every other one is spoiled." On examination of the ovaries after slaughtering, it was found that in the case of one of the carbonaceous fed hens the ovules were in a more advanced stage, but on the whole the nitrogenous fed hens were much nearer the laying period. With this single exception, the clusters of ovules in the carbonaceous fed hens were uniformly small. Neither group would have laid under any probability for several weeks. It would seem from these facts, together with the fact that during the experiment the nitrogenous fed hens laid more than three times as many eggs, that a nitrogenous ration stimulates egg production.

THE RESULTS OF SLAUGHTERING.

On November 27 the fowls were slaughtered. Each fowl was weighed, wrapped in a bag to prevent floundering, and killed by severing an artery in the roof of the mouth. The blood was caught in a glass jar. The fowls were then picked and the feathers weighed, after which the body was laid open longitudinally by cutting alongside the sternum and through the back bone. When all had been thus prepared, they were hung up in groups to be photographed, but the photographs were quite unsatisfactory so far as showing the relative proportions of fat and lean. The accompanying drawing made from the photograph shows the relative development of an average pair of chickens. Attention is particularly called to the thighs.

One-half of each fowl was tested by cooking for flavor, succulence, and tenderness. The other half was carefully prepared for chemical analysis by separating the meat from the bones. The flesh was thoroughly mixed and run through a sausage cutter, mixed again, and the process repeated three times. From different parts of this mixture a large sample was taken, from which the chemist took his samples for analysis. The right tibia of each fowl was tested for strength by placing it across two parallel bars and suspending a wire on its center, on which were placed small weights until the bone gave way.

DRESSED WEIGHT, INTERNAL ORGANS, ETC.
____________________________________________________________________
| |
| Hens. | Chickens.
|___________________|____________________
| | | |
| Lot I. | Lot II. | Lot I. | Lot II.
| Nitro- | Carbon- | Nitro- | Carbon-
| genous. | aceous. | genous. | aceous.
|_________|_________|_________|__________
| lb. | lb. | lb. | lb.
Live weight. | 21.31 | 22.0 | 17.89 | 12.63
Dressed weight. | 14.86 | 15.09 | 12.01 | 8.89
" " per cent. | 69.7 | 68.6 | 67.1 | 70.5
Weight of blood. | 0.75 | 0.66 | 0.55 | 0.34
" " feathers. | 1.41 | 1.25 | 1.28 | 0.66
" " intestinal fat. | 0.59 | 1.98 | 0.34 | 0.66
" " offal. | 3.70 | 3.02 | 3.62 | 2.08
" " bones. | 3.47 | 3.63 | 3.18 | 2.69
" " flesh. | 11.39 | 11.47 | 8.93 | 6.20
___________________________|_________________________________________

The breaking strain of the right tibia was as follows for the hens and chickens of the various lots:

Average hens, nitrogenous. 48.16
" " carbonaceous. 51.74
" chickens, nitrogenous. 46.64
" " carbonaceous. 31.18

There was little difference in the strength of the bones of the hens, undoubtedly because the bones were mature before the feeding began, and were little affected by the feeding. We find, however, that the bones of the chickens fed on nitrogenous food were almost fifty per cent. (49.6) stronger than those fed carbonaceous food.

The difference in the composition of the flesh, as shown by the analysis of Mr. W.P. Cutter, is given below:

__________________________________________________________________
| |
| Hens. | Chickens.
|___________________|____________________
| | | |
| Lot I. | Lot II. | Lot I. | Lot II.
| Nitro- | Carbon- | Nitro- | Carbon-
| genous. | aceous. | genous. | aceous.
|_________|_________|_________|__________
Albuminoids. | 43.81 | 25.13 | 52.00 | 30.06
Fat. | 12.59 | 20.76 | 5.54 | 11.34
_________________________________________________________________

The flesh of each group was submitted to a number of persons for a cooking test, and the almost unanimous verdict was that the flesh of the fowls fed a nitrogenous ration was darker colored, more succulent, more tender, and better flavored, though on this last there was some difference of opinion.

CONCLUSIONS.

So far as it is warrantable to draw any conclusions from a single experiment of this kind, it would seem that:

Chickens fed on an exclusive corn diet will not make a satisfactory development, particularly of feathers.

The bones of chickens fed upon a nitrogenous ration are fifty per cent. stronger than those fed upon a carbonaceous ration.

Hens fed on a nitrogenous ration lay many more eggs but of smaller size and poorer quality than those fed exclusively on corn.

Hens fed on corn, while not suffering in general health, become sluggish, deposit large masses of fat on the internal organs, and lay a few eggs of large size and excellent quality.

The flesh of nitrogenous fed fowls contains more albuminoids and less fat than those fed on a carbonaceous ration, and is darker colored, juicier and tenderer.

I.P. ROBERTS, Director.

* * * * *

HERBACEOUS GRAFTING.

My attention has been called a number of times to the unsatisfactory records and directions concerning the grafting of herbaceous plants. There appears to have been very little attention given to the subject, and the scant discussions of it are mostly copied from one author to another. A few years ago I made some attempts at herbaceous grafting, but it was not until last winter that experiments were seriously undertaken. The work was put in the hands of J.R. Lochary as a subject for a graduating thesis.

The experiments were undertaken primarily for the purpose of learning the best methods of grafting herbs, but a secondary and more important object was the study of the reciprocal influences of stock and cion, particularly in relation to variegation and coloration. This second feature of the work is still under way, in one form or another, and we hope for definite results in a few years. As a matter of immediate advantage, however, herbaceous grafting has its uses, particularly in securing different kinds of foliage and flowers upon the same plant. There is no difficulty in growing a half dozen kinds or colors, on geraniums, chrysanthemums, or other plants from one stock of the respective species.

Six hundred grafts were made in our trials last winter. It was found that the wood must be somewhat hardened to secure best results. The very soft and flabby shoots are likely to be injured in the operation of grafting, and union does not take place readily. Vigorous coleus stocks, three months old, gave best results if cut to within two or three inches of the pot and all or nearly all the leaves removed from the stump. Geraniums, being harder in wood, made good unions at almost any place except on the soft growing points. The stock must not have ceased growth, however. Most of the leaves should be kept down on the stock. Cions an inch or two long were usually taken from firm growing tips, in essentially the same manner as in the making of cuttings. Sometimes an eye of the old wood was used, and in most cases union took place and a new shoot arose from the bud. The leaves were usually partly removed from the cion.

Various styles of grafting were employed, of which the common cleft and the veneer or side graft were perhaps the most satisfactory. In most instances it was only necessary to bind the parts together snugly with bass or raffia. In some soft wooded plants, like coleus, a covering of common grafting wax over the bandage was an advantage, probably because it prevented the drying out of the parts. In some cases, however, wax injured the tissues where it overreached the bandage. Sphagnum moss was used in many cases tied in a small mass about the union, but unless the parts were well bandaged the cion sent roots into the moss and did not unite, and in no case did moss appear to possess decided advantages. Best results were obtained by placing the plants at once in a propagating frame, where a damp and confined atmosphere could be obtained. In some plants, successful unions were made in the open greenhouse, but they were placed in shade and kept sprinkled for a day after the grafts were made. The operation should always be performed quickly to prevent flagging of the cions. Or, if the cions cannot be used at once, they may be thrust into sand or moss in the same manner as cuttings, and kept for several days. In one series, tomato and potato cuttings, which had flagged in the cutting bed, revived when grafted. And cuttings which had been transported in the mail for three days grew readily, but they were in good condition when received. The mealy bugs were particularly troublesome upon these grafted plants, for they delighted to crawl under the bandages and suck the juices from the wounded surfaces.

Although it is foreign to the purpose of this note, it may be worth while to mention a few of the plants upon which the experiments were made. Sections were taken of many of the grafts and microscopic examinations made to determine the extent of cell union. Coleuses of many kinds were used, with uniform success, and the cions of some of them were vigorous a year after being set. Even iresine (better known as _Achyranthes Verschaffeltii_) united with coleus and grew for a time. Zonale geraniums bloomed upon the common rose geranium. Tomatoes upon potatoes and potatoes upon tomatoes grew well and were transplanted to the open ground, where they grew, flowered and fruited until killed by frost. The tomato-on-potato plants bore good tomatoes above and good potatoes beneath, even though no sprouts from the potato stock were allowed to grow. Peppers united with tomatoes and tomatoes united with peppers. Egg plants, tomatoes and peppers grew upon the European husk tomato or alkekengi (_Physalis Alkekengi_). Peppers and egg plants united with each other reciprocally. A coleus cion was placed upon a tomato plant and was simply bound with raffia. The cion remained green and healthy, and at the end of forty-eight days the bandage was removed, but it was found that no union had taken place. Ageratums united upon each other with difficulty. Chrysanthemums united readily. A bean plant, bearing two partially grown beans, chanced to grow in a chrysanthemum pot. The stem bearing the pods was inarched into the chrysanthemum. Union took place readily, but the beans turned yellow and died. Pumpkin vines united with squash vines, cucumbers with cucumbers, muskmelons with watermelons, and muskmelons, watermelons and cucumbers with the wild cucumber or balsam apple (_Echinocystis lobata_).

Another interesting feature of the work was the grafting of one fruit upon another, as a tomato fruit upon a tomato fruit or a cucumber upon another cucumber. This work is still under progress and it promises some interesting results in a new and unexpected direction, reports of which may be expected later.--_Cornell Station Bulletin_.

* * * * *

A HUMOROUS HEALTH OFFICER.

The Michigan State Board of Health recently took Health Officer Davis, of Close Village, to task for failing to send in his weekly reports. His reply was unique. He says: "There has not been enough sickness here the last two or three years to do much good. The physicians find time to go to Milwaukee on excursions, serve as jurors in justice courts, sit around on drygoods boxes, and beg tobacco, chew gum, and swap lies. A few sporadic cases of measles have existed, but they were treated mostly by old women, and no deaths occurred. There was an undertaker in the village, but he is now in the State prison. It is hoped and expected when green truck gets around, melons plenty, and cucumbers in abundance, that something may revive business. If it does, I will let you know."

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