Chapter I (5)

(391.) Finally, when we look back on what has been accomplished in science, and compare it with what remains to be done, it is hardly possible to avoid being strongly impressed with the idea that we have been and are still executing the labour by which succeeding generations are to profit.[61] In a few instances only have we arrived at those general axiomatic laws which admit of direct deductive inference, and place the solutions of physical phenomena before us as so many problems, whose principles of solution we fully possess, and which require nothing but acuteness of reasoning to pursue even into their farthest recesses. In fewer still have we reached that command of abstract reasoning itself which is necessary for the accomplishment of so arduous a task. Science, therefore, in relation to our faculties, still remains boundless and unexplored, and, after the lapse of a century and a half from the æra of Newton’s discoveries, during which every department of it has been cultivated with a zeal and energy which have assuredly met their full return, we remain in the situation in which he figured himself,--standing on the shore of a wide ocean, from whose beach we may have culled some of those innumerable beautiful productions it casts up with lavish prodigality, but whose acquisition can be regarded as no diminution of the treasures that remain.

(392.) But this consideration, so far from repressing our efforts, or rendering us hopeless of attaining any thing intrinsically great, ought rather to excite us to fresh enterprise, by the prospect of assured and ample recompense from that inexhaustible store which only awaits our continued endeavours. “It is no detraction from human capacity to suppose it incapable of infinite exertion, or of exhausting an infinite subject.”[62] In whatever state of knowledge we may conceive man to be placed, his progress towards a yet higher state need never fear a check, but must continue till the last existence of society.

(393.) It is in this respect an advantageous view of science, which refers all its advances to the discovery of general laws, and to the inclusion of what is already known in generalizations of still higher orders; inasmuch as this view of the subject represents it, as it really is, essentially incomplete, and incapable of being fully embodied in any system, or embraced by any single mind. Yet it must be recollected that, so far as our experience has hitherto gone, every advance towards generality has at the same time been a step towards simplification. It is only when we are wandering and lost in the mazes of particulars, or entangled in fruitless attempts to work our way downwards in the thorny paths of applications, to which our reasoning powers are incompetent, that nature appears complicated:--the moment we contemplate it as it is, and attain a position from which we can take a commanding view, though but of a small part of its plan, we never fail to recognise that sublime simplicity on which the mind rests satisfied that it has attained the truth.

INDEX.

Acoustics cultivated by Pythagoras and Aristotle, page 248.

Æpinus, his laws of equilibrium of electricity, 332.

Aëriform fluids, liquids kept in a state of vapour, 321.

Agricola, George, his knowledge of mineralogy and metallurgy, 112.

Air, compressibility and elasticity of; limitation to the repulsive
tendency of, 226.
Weight of, unknown to the ancients, 228.
First perceived by Galileo, 228.
Proved by a crucial instance, 229.
Equilibrium of, established, 231.
Dilatation of, by heat, 319.

Air-pump, discovery of, 230.

Airy, his experiments in Dolcoath mine, 187.

Alchemists, advantages derived from, 11.

Algebra, 19.

Ampere, his electro-dynamic theory, 202.
Utility of, 203, 324.

Analysis of force, 86.
Of motion, 87.
Of complex phenomena, 88.

Anaxagoras, philosophy of, 107.

Animal electricity, 337.

Arago, M., his experiment with a magnetic needle and a plate of
copper, 157.

Archimedes, his practical application of science, 72.
His knowledge of hydrostatics, 231.

Arfwedson, his discovery of lithia, 158.

Aristotle, his knowledge of natural history, 109.
His works condemned, and subsequently studied with avidity, 111.
His philosophy overturned by the discoveries of Copernicus, Kepler,
and Galileo, 113.

Arithmetic, 19.

Art, empirical and scientific, differences between, 71.
Remarks on the language, terms, or signs, used in treating of
it, 70.

Assurances, life, utility and abuses of, 58.

Astronomy, cause of the slow progress of our knowledge of, 78.
Theory and practical observations distinct in, 132.
An extensive acquaintance with science and every branch of knowledge
necessary to make a perfect observer in, 132.
Five primary planets added to our system, 274.
Positions, figures, and dimensions of all the planetary orbits now
well known, 275.

Atomic theory, 305.
Advantage of, 306.

Atomic weights of chemical elements, 306.

Attraction, capillary, or capillarity, investigated by Laplace and
Young, 234.

Bacon, celebrated in England for his knowledge of science, 72.
Benefits conferred on Natural Philosophy by him, 104.
His Novum Organum, 105.
His reform in philosophy proves the paramount importance of
induction, 114.
His prerogative of facts, 181.
Illustrated by the fracture of a crystallized substance, 183.
His collective instances, 184.
Importance of, 185.
His experiment on the weight of bodies, 186.
Travelling instances of, frontier instances of, 188.
His difference between liquids and aëriform fluids, 233.

Bartolin, Erasmus, first discovers the phenomena exhibited by doubly
refracting crystals, 254.

Beccher, phlogistic doctrines of, 300.

Bergmann, his advancement in crystallography, 239.

Bernoulli, experiments of, in hydrodynamical science, 181.

Biot, his hypothesis of a rotatory motion of the particles of light
about their axes, 262.

Black, Dr., his discovery of latent heat, 322.

Bode, his curious law observed in the progression of the magnitudes of
the several planetary orbits, 308.

Bodies, natural constitution of, 221.
Division of, into crystallized and uncrystallized, 242.

Bones, dry, a magazine of nutriment, 65.

Borda, his invention for subdivision, 128.

Botany, general utility of, 345.

Boyle, Robert, his enthusiasm in the pursuit of science, 115.
His improvement on the air-pump, 230.

Brain, hypothesis of its being an electric pile, 343.

Bramah’s press, principle and utility of, 233.

Brewster, Dr., his improvement on lenses for lighthouses, 56.
His researches prove that the phenomena exhibited by polarized
light, in its transmission through crystals, afford a certain
indication of the most important points relating to the
structure of crystals themselves, 263.

Cabot, Sebastian, his discovery of the variation of the needle, 327.

Cagnard, Baron de la Tour, utility of his experiments, 234.

Causes and consequences directors of the will of man, 6.

Causes, proximate, discovery of, called by Newton _veræ causæ_, 144.

Celestial mechanics, 265.

Chaldean records, 265.

Chemistry furnishes causes of sudden action, also fulminating
compositions, 62.
Analogy of the complex phenomena of, with those of physics, 92.
Benefits arising from the analysis of, 94.
Axioms of, analogous to those of geometry, 95.
Many of the new elements of, detected in the investigation of
residual phenomena, 158.
The most general law of, 209.
Illustration of, 210.
Between fifty and sixty elements in, 211.
Objects of, 296.
General heads of the principal improvements in, 302.
Remarks on those general heads, 304.

Chemistry, Stahlian, cause of the mistakes and confusions of, 123.

Chladni, experiments of, in dynamical science, 181.

Chlorine, disinfectant powers of, 56.

Clarke, Dr., his experiments on the arseniate and phosphate
of soda, 170.
His success in producing a new phosphate of soda, 171.

Climate, change of, in large tracts of the globe, alleged
cause of, 145.

Coals, power of a bushel of, properly consumed, 59.
Quantity consumed in London, 60.

Cohesion, an ultimate phenomenon, 90.

Cold, qualities of, 318.

Compass, mariner’s, 55.

Condensation, a source of heat, 313.

Conduction of heat, laws of, 205.

Copernicus, effect of his discoveries on the Aristotelian
philosophy, 113.
Objections to his astronomical doctrines, 269.

Crystallography, laws of, 123, 239.
A determinate figure supposed to be common to all the particles of a
crystal, 242.

D’Alembert, his improvements in hydrodynamics, 236.

Dalton, his announcement of the atomic theory, 305.
His examination of gases and vapours, 319.

Davy, Sir H., brings the voltaic pile to bear upon the earths and
alkalies, 339.

Deduction, utility of, 174.

De l’Isle, Romé, his study of crystalline bodies, 239.

Dew, causes of, investigated, 159.
Effects of, on different substances, 160.
Objects capable of contracting it, 161.
A cloudless sky favourable to its production, 162.
General proximate cause of, 163.

Drummond, lieutenant, his improvement on lenses for lamps of
lighthouses, 56.

Dynamics, importance of, 96, 223.

Earth, the orbit of,--diminution of its eccentricity round
the sun, 147.

Economy, political, 73.

Egypt, great pyramid of, height, weight, and ground occupied by
it, 60.
Accuracy of the astronomical records of, 265.

Elasticity, an ultimate phenomenon, 90.

Electricity may be the cause of magnetism, 93.
Universality of, 329.
Effects of, 330.
Activity of, 331.
Equilibrium of, 332.
Productive of chemical decomposition, 338.

Empirical laws, 178.
Evils resulting from, 179.

Encke, professor, his prediction of the return of the comet so many
times in succession, 156.

Englefield, sir H., his analysis of a solar beam, 314.

Equilibrium maintained by force, 222.

Erman, professor, his opinion of the effects of the voltaic
circuit, 340.

Euler, his improvement on Newton’s theory of sound, 247.

Experience, source of our knowledge of nature’s laws, 76.

Experiment, a means of acquiring experience, 76.
Utility of, 151.

Facts, the observation of, 118.

Faujas de St. Fond, imaginary craters of, 131.

Fluids, laws of the motion of, 181.
Compressibility of, 225.
Consideration of the motions of, more complicated than that of
equilibrium, 235.

Force, analysis of, 86.
The cause of motion, 149.
Phenomena of, 221.
Molecular forces, 245.

Fourier, baron, his opinion that the celestial regions have a
temperature, independent of the sun, not greatly inferior
to that at which quicksilver congeals, 157.
His analysis of the laws of conduction and radiation of heat, 317.

Franklin, Dr., his experiments on electricity, 332.

Fresnel, M., his mathematical explanation of the phenomena of double
refraction, 32.
His improvement on lenses for lamps of lighthouses, 56.
His opinions on the nature of light, 207.
His experiments on the interference of polarized light, 261.
His theory of polarization, 262.

Friction, a source of heat, 313.

Galileo, celebrity of, for his knowledge of science, 72.
His exposition of the Aristotelian philosophy, 110.
His refutation of Aristotle’s dogmas respecting motion, his
persecution in consequence of it, 113.
His knowledge of the accelerating power of gravity, 168.
His knowledge of the weight of the atmosphere, 228.

Galvani, utility of his discoveries in electricity, 335.
His application of it to animals, 336.

Gay-Lussac, his examination of gases and vapours, 319.

Generalization, inductive, 1, 90.

Geology, 281.
Its rank as a science, 287.

Geometry, axioms of, an appeal to experience, not corporeal, but
mental, 95.

Gilbert, Dr., of Colchester, his knowledge of magnetism and
electricity, 112.

Gravitation, law of, a physical axiom of a very high and universal
kind, 98.
Influence of, decreases in the inverse ratio of the square of the
distance, 123.

Greece, philosophers of, their extraordinary success in abstract
reasoning, and their careless consideration of external
nature, 105.
Their general character, 106.
Philosophy of, 108.

Grimaldi, a jesuit of Bologna, his discovery of diffraction, or
inflection of light, 252.

Guinea and feather experiment, 168.

Gunpowder, invention of, 55.
A mechanical agent, 62.

Haarlem lake, draining of, 61.

Harmony, sense of, 248.

Head, captain, anecdote of, 84.

Heat, 193.
Radiation and conduction of, 205.
One of the chief agents in chemistry, 310.
Our ignorance of the nature of, 310.
Abuse of the sense of the term, 311.
The general heads under which it is studied, 312.
Its most obvious sources, 312.
Animal heat, to what process referable, 313.
Radiation and conduction of, 314.
Solar heat differs from terrestrial fires, or hot bodies, 315.
Principal effects of, 317.
The antagonist to mutual attraction, 322.
Latent heat, 322.
Specific heat, 323.

Herschel, sir William, his analysis of a solar beam, 314.

Hipparchus, his catalogue of stars, 276.

Holland drained of water by windmills, 61.

Hooke almost the rival of Newton, 116.

Huel Towan, steam-engine at, 59.

Huyghens, his doctrine of light, 207.
Ascertains the laws of double refraction, 254.

Hydrostatics, first step towards a knowledge of, made by
Archimedes, 231.
Law of the equal pressure of liquids, 232.
General applicability of, 232.

Hypothesis, not to be deterred from framing them, 196.
Conditions on which they should be framed, 197.
Illustrated by the laws of gravitation, 198.
Use and abuse of, 204.

Induction, different ways of carrying it on, 102.
Steps by which it is arrived at on a legitimate and extensive
scale, 118.
First stage of, 144.
Verification of, 164.
Instanced in astronomy, 166.
Must be followed into all its consequences, and applied to all those
cases which seem even remotely to bear upon the subject of
enquiry, 173.
Nature of the inductions by which quantitative laws are arrived
at, 176.
Necessity of induction embracing a series of cases which absolutely
include the whole scale of variation of which the quantities
in question admit, 177.

Induced electricity, 333.

Inertia, 223.

Iodine, discovery of, 50.
Efficacy of, in curing goître, 51.

Isomorphism, law of, 170.

Kepler, effect of his discoveries on the Aristotelian philosophy, 113.
Nature of his laws of the planetary system, 178.
Proofs of the Newtonian system, 179.

Knowledge, physical facts illustrative of the utility of, 45.
Diffusion of, how to take advantage of in the investigation of
nature, 138.

Lagrange, his improvements on Newton’s theory of sound, 247.
His astronomical researches, 275.

Lamp, safety, 55.

Laplace, his explanation of the residual velocity of sound and
confirmation of the general law of the developement of heat
by compression, 172.
His astronomical research, 275.
His experiments on the dilatation of bodies by heat, 319.
His study of specific heat, 323.
Latent heat, 323.

Laws, inductive, 171.
General, 198.
How applicable, 199.
Illustrated by the planetary system, 201.
Empirical laws, 178.

Lavoisier, his improvements in chemical science, 302.
Experiments on dilatation of bodies by heat, 319.
His investigation on specific heat, 323.

Light, refraction of, 30.
Double refraction of, 31.
Polarization of, 254.

Light and vision, ignorance of the ancients respecting, 249.

Lighthouse, 56.

Lightning, how to judge philosophically of it, 120.
Returning stroke of, 121.

Liquids, cohesion, attraction and repulsion of the particles of, 227.
Differ from aëriform fluids by their cohesion, 233.
The Florentine experiment on; experiments by Canton, Perkins,
Oërsted, and others on, 235.
Obscurity of the laws of dilatation of, 320.

Linnæus, his knowledge of crystalline substances, 239.

Logic, 19.

Lyell’s Principles of Geology, extract from, 146.

Magnetism may be caused by electricity, 93.
Offers a “glaring instance” of polarity, 326.
Experiments illustrative of, 327.

Malus, a French officer of engineers, discovers the polarization of
light, 132, 258.

Man, regarded as a creature of instinct, 1.
Of reason and speculation, 3.
His will determined by causes and consequences, 6.
Advantages to, from the study of science, 7.
His necessity to study the laws of nature illustrated, 66.
Happiness and the opposite state of man in the aggregate, 67.
Advantages conferred on, by the augmentation of physical
resources, 68.
Advantages from intellectual resources, 69.

Mariotte, his law of equilibrium of an elastic fluid recently verified
by the Royal Academy of Paris, 231.
His difference between solar and other heat, 315.

Matter, indestructibility of; Divided by grinding, 40.
By fire, 41.
Dilated by heat, 193.
Inertia of, 202.
Polarity of, one of the ultimate phenomena to which the analysis of
nature leads us, 245.
Inherent activity of, 297.
Causes of the polarity of, 299.
Imponderable forms of, 310.

Measure, the standard, difficulty of preserving it unaltered, 128.
How to be assisted in measurement, 129.
Our conclusions from, should be conditional, 130.

Menai Bridge, weight and height of, 60.

Mechanics, practical, 63.

Mètre, the French, 126.

Microscopes, power of, 191.

Millstones, method of making in France, 48.

Mind, its transition from the little to the great, and _vice versâ_,
illustrated, 172.

Mineralogy unknown to the ancients, 79.
Prejudiced by the rage for nomenclature, 139.
Benefited by the progress of chemical analysis, 293.

Minerals, simple, apparent paucity of, 294.
Difficulty in classing them, 295.

Mitscherlich, his law of isomorphism, 170.
His experiments on the expansion of substances by heat, 243.

Motion, 87.
Simplicity and precision of the laws of, 179.

Nature, laws of, 37.
Immutability of, 42.
Harmony of, and advantage of studying them, 43.
Prove the impossibility of attaining the declared object of the
alchemist. How they serve mankind generally, 44.
Illustrated by mining, 45.
Economy derived from a knowledge of, 65.
How to be regarded, 100, 101.

Nature, objects of, an enumeration and nomenclature of, useful in the
study of, 135.
Mechanism of, on too large or too small a scale to be immediately
cognisable by our senses, 191.

Newton, his proof of Galileo’s laws of gravitation by an experiment
with a hollow glass pendulum, 160.
His foundation to hydrodynamical science, 181.
Fixes the division between statics and dynamics, 223.
His investigation of the law of equilibrium of elastic fluids, 231.
His law of hydrostatics, 232.
His foundation of hydrodynamics 236.
His analysis of sound, 247.
Hypothesis of light, 250.
Examination of a soap-bubble, 252.
His hypothesis of fits of easy transmission and reflection, 253.
His combination of mathematical skill with physical research, 271.
His Principia, 272.
His successors; his geometry, 273.

Nomenclature, importance of, to science, 136.
More a consequence than a cause of extended knowledge, 138.
Prejudicial to mineralogy, 139.

Norman, Robert, his discovery of the dip of the needle, 327.

Numerical precision, necessity of, in science, 122.

Objects, and their mutual actions, subjects of contemplation, 118.

Observation, a means of acquiring experience, 76.
Passive and active, 77.
Recorded observation, 120.
Necessity of, to acquire precise physical data, 215.
Illustrated by the barometer, 216.

Oërsted, his discoveries in electricity and magnetism, 132.
Of electro-magnetism, 340.

Opacity, 189.

Otto von Guericke of Magdeburgh, his invention of the air-pump, 230.

Paracelsus, power of his chemical remedies; his use of mercury,
opium, and tartar, 112.

Pascal, his crucial instances proving the weight of air, 229.

Pendulum, 126.

Phenomena, analysis of, illustrated by musical sounds, the sensation
of taste, 85.
The ultimate and inward process of nature in the production of, 86.
Analysis of complex phenomena, 88.
Ultimate phenomena, 90.
How the analysis of, is useful, 97.
A transient phenomenon, how to judge of, 122.
Method of explaining one when it presents itself, 148.
How to discover the cause of one, 150.
Two, or many, theories, maintained as the origin of, in
physics, 195.
Cosmical phenomena, 265.

Philosophy, natural, unfounded objections to the study of, 7.
Advantages derivable from the study of, 10.
Pleasure and happiness, the consequences of the study of, 15.

Phlogistic doctrines of Beccher and Stahl, 300.

Physical data, necessity of, 209.
Great importance of, 211.
Illustrated by the erection of observatories, 213.
Necessity of an exact knowledge of, 214.
More precise than the observations by which we acquire them, 215.

Physics, axioms of; analysis of, 102.

Planets, circumjovial, 186.

Platina, discovery of, 308.

Pliny, his knowledge of quartz and diamond, 239.

Pneumatics, 228.

Political economy, 73.

Prejudices of opinion and sense, 80.
Conditions on which such are injurious, 81.
Illustrated by the division of the rays of light, by the moon at the
horizon, and by ventriloquism, 82.
By the transition of the hand from heat to cold, 83.

Prevost, M., his theory of heat, 316.
His theory of reciprocal interchanges, a proof of the radiation
of cold, 318.

Printing, the art of, 193.
Performed by steam, 194.

Probabilities, doctrine of, 217.
Illustrated by shooting at a wafer, 218.

Prout, Dr., his opinion of the atomic weights, 307.

Pyrometry, 319.

Pythagoras, philosophy of, 107.

Quinine, sulphate of, comparative comfort and health resulting from
the use of, 56.

Radiation of heat, laws of, 205.

Repulsion in fluids and solids, 227.

Rules, general, for guiding and facilitating our search among a great
mass of assembled facts, 151.

Rumford, count, experiments of, on gunpowder, 62.

Savart, M., his experiments on solids, 243.
His researches on sound, 249.

Science, abstract, a preparation for the study of physics, 19.
Not indispensable to the study of physical laws, 25.
Instances illustrative of, 27.

Science, physical, nature and objects, immediate and collateral, as
regarded in itself and in its application to the practical
purposes of life, and its influence on society, 35.
State of, previous to the age of Galileo and Bacon, 104.
Causes of the rapid advance of, compared with the progress at an
earlier period, 347.

Science, natural, cause and effect, the ultimate relations of, 76.

Sciences and Arts, remarks on the language, terms, or signs used in
treating of them, 70.
Receive an impulse by the Baconian philosophy, 114.

Sensation, cause of, 91.

Senses, inadequate to give us direct information for the exact
comparison of quantity, 124.
Substitutes for the inefficiency of, 125.

Seringapatam, method of breaking blocks from the quarries of, 47.

Shells found in rocks at a great height above the sea, supposed
cause of, 145.

Smeaton, his experiments on bodies dilated by heat, 319.

Solids, transparent, exhibit periodical colours when exposed to
polarized light, 99.
Influence of, on the Mind, 101.

Solids in general, nature of, 236.
Constitution of, complicated, 237.
Toughness of, distinct from hardness; tenacity of, 238.
Become liquefied by the addition of heat, 321.

Sounds, musical, illustrative of the analysis of phenomena, 85.
Means of having a knowledge of, 89.
Propagation of, through the air, 246.
Newton’s analysis of, 247.

Standard measurement, necessity of, 125.
Laws of nature used as such, illustrated by the rotation of the
earth, 126.

Substances all subject to dilatation by the addition of heat, 243.

Sun, the character of the heat of, 315.

Thales, philosophy of, 107.

Theories, how to estimate the value of, 204.
Best arrived at by the consideration of general laws, 208.
Explanatory of the phenomena of nature; on what their application
ought to be grounded, 209.

Thomson, Dr., his opinion of the atomic weights, 307.

Thermometer, air, 319.

Thermo-electricity, 341.

Time, division of, 126, 127.

Torricelli, pupil of Galileo, his experiments proving the weight of
atmosphere, 229.

Torpedo, shock of, 341, 342.

Ulugh Begh, his catalogue of stars, 277.

Vaccination, success of, as a preventive to small-pox, 52.

Vision and light, ignorance of the ancients respecting, 249.

Volta, his discoveries in electricity, 335.
Electric pile of, 337.

Voltaic circuit, 338.

Water, effects of the power of, 61.

Whewell, his experiments, 187.

Wells, Dr., his theory of dew, 163.

Wind, effects of the power of, 61.

Wire steel, magnetized masks of, used by needle-makers, 57.

Wollaston, Dr., his verification of the laws of double refraction in
Iceland spar, 258.
His invention of the goniometer, 292.

World, the materials of the, 290.

Young, Dr., his experiments on the interference of the rays of
light, 260.

Zoology, fossil, 344.

THE END.

LONDON
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FOOTNOTES

[1] Hooke’s Posthumous Works. Lond. 1705.--p. 472 and p. 458.

[2] Wealth of Nations, book i. chap. i. p. 15.

[3] On this subject, we cannot forbear citing a passage from one of the most profound but at the same time popular writers of our time, on a subject unconnected it is true with our own, but bearing strongly on the point before us. “But, if science be manifestly incomplete, and yet of the highest importance, it would surely be most unwise to restrain enquiry, conducted on just principles, even where the immediate practical utility of it was not visible. In mathematics, chemistry, and every branch of natural philosophy, how many are the enquiries necessary for their improvement and completion, which, taken separately, do not appear to lead to any specifically advantageous purpose! how many useful inventions, and how much valuable and improving knowledge, would have been lost, if a rational curiosity, and a mere love of information, had not generally been allowed to be a sufficient motive for the search after truth!”--Malthus’s Principles of Political Economy, p. 16.

[4] Λογος, _ratio_, reason.

[5] Λογος, _verbum_, a word.

[6] It were much to be wished that navigators would be more cautious in laying themselves open to a similar censure. On looking hastily over a map of the world we see three Melville Islands, two King George’s Sounds, and Cape Blancos innumerable.

[7] Young. Lectures on Nat. Phil. ii. 627. See also Phil. Trans. 1801-2.

[8] Captain Basil Hall, R. N.

[9] We must caution our readers who would assure themselves of it by trial, that it is an experiment of some delicacy, and not to be made without several precautions to ensure success. For these we must refer to our original authority (Fresnel. Mémoire sur la Diffraction de la Lumiere, p. 124.); and the principles on which they depend will of course be detailed in that volume of the Cabinet Cyclopædia which is devoted to the subject of LIGHT.

[10] Little reels used in cotton mills to twist the thread.

[11] Such a block would weigh between four and five hundred thousand pounds. See Dr. Kennedy’s “Account of the Erection of a Granite Obelisk of a Single Stone about Seventy Feet high, at Seringapatam.”--_Ed. Phil. Trans._ vol. ix, p. 312.

[12] Dr. Coindet of Geneva.

[13] Journal of a Voyage to the South Seas, &c. &c. under the Command of Commodore George Anson, in 1740-1744, by Pascoe Thomas, Lond. 1745, So tremendous were the ravages of scurvy, that, in the year 1726, admiral Hosier sailed with seven ships of the line to the West Indies, and buried his ships’ companies twice, and died himself in consequence of a broken heart. Dr. Johnson, in the year 1778, could describe a sea-life in such terms as these:--“As to the sailor, when you look down from the quarter deck to the space below, you see the utmost extremity of human misery, such crowding, such filth, such stench!”--“A ship is a prison with the chance of being drowned--it is worse--worse in every respect--worse room, worse air, worse food--worse company!” Smollet, who had personal experience of the horrors of a seafaring life in those days, gives a lively picture of them in his Roderick Random.

[14] Lemon juice was known to be a remedy for scurvy far superior to all others 200 years ago, as appears by the writings of Woodall. His work is entitled “The Surgeon’s Mate, or Military and Domestic Medicine. By John Woodall, Master in Surgery London, 1636,” p. 165. In 1600, Commodore Lancaster sailed from England with three other ships for the Cape of Good Hope, on the 2d of April, and arrived in Saldanha Bay on the 1st of August, the commodore’s own ship being in perfect health, from the administration of three table-spoonsfull of lemon juice every morning to each of his men, whereas the other ships were so sickly as to be unmanageable for want of hands, and the commander was obliged to send men on board to take in their sails and hoist out their boats. (Purchas’s Pilgrim, vol. i. p. 149.) A Fellow of the college, and an eminent practitioner, in 1753 published a tract on sea scurvy, in which he adverts to the superior virtue of this medicine; and Mr. A. Baird, surgeon of the Hector sloop of war, states, that from what he had seen of its effects on board of that ship, he “thinks he shall not be accused of presumption in pronouncing it, if properly administered, a _most infallible remedy_, both in the cure and prevention of scurvy.” (Vide Trotter’s Medicina Nautica.) The precautions adopted by captain Cook in his celebrated voyages, had fully demonstrated by their complete success the practicability of keeping scurvy under in the longest voyages, but a uniform system of prevention throughout the service was still deficient.

It is to the representations of Dr. Blair and sir Gilbert Blane, in their capacity of commissioners of the board for sick and wounded seamen, in 1795, we believe, that its _systematic introduction into nautical diet_, by a general order of the admiralty, is owing. The effect of this wise measure (taken, of course, in conjunction with the general causes of improved health,) may be estimated from the following facts:--In 1780, the number of cases of scurvy received into Haslar hospital was 1457; in 1806 _one_ only, and in 1807 _one_. There are now many surgeons in the navy who have never seen the disease.

[15] Throughout France the conductor is recognised as a most valuable and useful instrument; and in those parts of Germany where thunder-storms are still more common and tremendous they are become nearly universal. In Munich there is hardly a modern house unprovided with them, and of a much better construction than ours--several copper wires twisted into a rope.

[16] We have been informed by an eminent physician in Rome, (Dr. Morichini) that a vast quantity of the sulphate of quinine is manufactured there and consumed in the Campagna, with an evident effect in mitigating the severity of the malarious complaints which affect its inhabitants.

[17] Dr. Johnson, Memoirs of the Medical Society, vol. v.

[18] The engine at Huel Towan. See Mr. Henwood’s Statement “of the performance of steam-engines in Cornwall for April, May, and June, 1829.” Brewster’s Journal, Oct. 1829.--The _highest_ monthly average of this engine extends to 79 millions of pounds.

[19] However, this is not quite a fair statement; a man’s daily labour is about 4 lbs. of coals. The extreme toil of this ascent arises from other obvious causes than the mere height.

[20] Its surface is about 40,000 acres, and medium depth about 20 feet. It was proposed to drain it by running embankments across it, and thus cutting it up into more manageable portions to be drained by windmills.

[21] No one doubts the _practicability_ of the undertaking. Eight or nine thousand chaldrons of coals duly burnt would evacuate the whole contents. But many doubt whether it would be profitable, and some, considering that a few hundreds of fishermen who gain their livelihood on its waters would be dispossessed, deny that it would be _desirable_.

[22] “Experiments to determine the Force of fired Gunpowder.” Phil. Trans. vol. lxxxvii. p. 254. et seq.

[23] See a very ingenious application of this kind in Mr. Babbage’s article on Diving in the Encyc. Metrop.--Others will readily suggest themselves. For instance, the ballast in reserve of a balloon might consist of materials capable of evolving great quantities of hydrogen gas in proportion to their weight, should such be found.

[24] The sulphuric. Bracconot, Annales de Chimie, vol. xii. p. 184.

[25] D’Arcet, Annales de l’Industrie, Fevrier, 1829.

[26] See Dr. Prout’s account of the experiments of professor Autenrieth of Tubingen. Phil. Trans. 1827, p. 381. This discovery, which renders famine next to _impossible_, deserves a higher degree of celebrity than it has obtained.

[27] Greenwich.

[28] Maskelyne’s.

[29] Thomson’s First Principles of Chemistry, vol. ii. p. 68.

[30] Galileo exposes unsparingly the Aristotelian style of reasoning. The reader may take the following from him as a specimen of its quality. The object is to prove the immutability and incorruptibility of the heavens; and thus it is done:--

I. Mutation is either generation or corruption.

II. Generation and corruption only happen between contraries.

III. The motions of contraries are contrary.

IV. The celestial motions are circular.

V. Circular motions have no contraries.

α. Because there can be but three simple motions.
1. To a centre.
2. Round a centre.
3. From a centre.

β. Of three things, one only can be contrary to one.

γ. But a motion to a centre is manifestly the contrary to a
motion from a centre.

δ. Therefore a motion _round_ a centre (_i. e._ a circular
motion) remains without a contrary.

VI. _Therefore_ celestial motions have no contraries--_therefore_
among celestial _things_ there are no contraries--_therefore_
the heavens are eternal, immutable, incorruptible, and so forth.

It is evident that all this string of nonsense depends on the excessive vagueness of the notions of generation, corruption, contrariety, &c. on which the changes are rung.--_See_ GALILEO, _Systema Cosmicum_, Dial. i. p. 30.

[31] Macquer justly observes, that the alchemists would have rendered essential service to chemistry had they only related their unsuccessful experiments as clearly as they have obscurely related those which they pretend to have been successful.--_Macquer’s Dictionary of Chemistry_, i. x.

[32] Paracelsus performed most of these cures by mercury and opium, the use of which latter drug he had learned in Turkey. Of mercurial preparations the physicians of his time were ignorant, and of opium they were afraid, as being “cold in the fourth degree.” Tartar was likewise a great favourite of Paracelsus, who imposed on it that name, “because it contains the water, the salt, the oil, and the acid, which burn the patient as hell does:” in short, a kind of counterbalance to his opium.

[33] See the Life of Galileo Galilei, by Mr. Drinkwater, with Illustrations of the Advancement of Experimental Philosophy.

[34] The temporary star in Cassiopeia observed by Cornelius Gemma, in 1572, was so bright as to be seen at noon-day. That in Serpentarius, first seen by Kepler in 1604, exceeded in brilliancy all the other stars and planets.

[35] Edinburgh Phil. Journ. 1819, vol. i. p. 8.

[36] The abstract principle of repetition in matters of measurement (viz. juxta-position of units without error) is applicable to a great variety of cases in which quantities are required to be determined to minute nicety. In chemistry, in determining the standard atomic weights of bodies, it seems easily and completely applicable, by a process which will suggest itself at once to every chemist, and seems the only thing wanting to place the exactness of chemical determinations on a par with astronomical measurements.

[37] Accurate and _perfectly_ authentic copies of the yard and pound, executed in platina, and hermetically sealed in glass, should be deposited deep in the interior of the massive stone-work of some great public building, whence they could only be rescued with a degree of difficulty sufficient to preclude their being disturbed unless on some very high and urgent occasion. The fact should be publicly recorded, and its memory preserved by an inscription. Indeed, how much valuable and useful information of the actual existing state of arts and knowledge at any period might be transmitted to posterity in a distinct, tangible, and imperishable form, if, instead of the absurd and useless deposition of a few coins and medals under the foundations of buildings, specimens of ingenious implements or condensed statements of scientific truths, or processes in arts and manufactures, were substituted. Will books infallibly preserve to a remote posterity all that we may desire should be hereafter known of ourselves and our discoveries, or all that posterity would wish to know? and may not a useless ceremony be thus transformed into an act of enrolment in a perpetual archive of what we most prize, and acknowledge to be most valuable?

[38] In the system alluded to, the name of quartz is assigned to iolite and obsidian; that of mica to plumbago, chlorite, and uranite; sulphur, to orpiment and realgar, &c. See Mohs’s System of Mineralogy, translated by Haidinger.

[39] The following passage, from Lindley’s Synopsis of the British Flora, characterises justly the respective merits, in a philosophical point of view, of natural and artificial systems of classification in general, though limited in its expression to his own immediate science:--“After all that has been effected, or is likely to be accomplished hereafter, there will always be more difficulty in acquiring a knowledge of the natural system of botany than of the Linnæan. The latter skims only the surface of things, and leaves the student in the fancied possession of a sort of information which it is easy enough to obtain, but which is of little value when acquired: the former requires a minute investigation of every part and every property known to exist in plants; but when understood has conveyed to the mind a store of real information, of the utmost use to man in every station of life. Whatever the difficulties may be of becoming acquainted with plants according to this method, they are inseparable from botany, which cannot be usefully studied without encountering them.” Schiller has some beautiful lines on this, entitled “Menschliches Wissen” (or Human Knowledge); Gedichte, vol. i. p. 72. Leipzig, 1800.

[40] Lyell’s Principles of Geology, vol. i. Fourrier, Mém. de l’Acad. des Sciences, tom. vii. p. 592. “L’établissement et le progrès des sociétés humaines, l’action des forces naturelles, peuvent changer notablement, et dans de vastes contrées, l’état de la surface du sol, la distribution des eaux, et les grands mouvemens de l’air. De tels effets sont propres à faire varier, dans le cours de plusieurs siècles, le dégré de la chaleur moyenne; car les expressions analytiques comprennent des coefficiens qui se rapportent à l’état superficiel, et qui influent beaucoup sur la valeur de la température.” In this enumeration, by M. Fourrier, of causes which may vary the general relation of the surface of extensive continents to heat, it is but justice to Mr. Lyell to observe, that the gradual shifting of the _places_ of the continents themselves on the surface of the globe, by the abrading action of the sea on the one hand, and the elevating agency of subterranean forces on the other, does not expressly occur and cannot be fairly included in the general sense of the passage, which confines itself to the consideration of such changes as may take place on the existing surface of the land.

[41] The reader will find this subject further developed in a paper lately communicated to the Geological Society.

[42] Phil. Trans. 1824.

[43] Wells on Dew.

[44] Principia, book iii. prop. 6.

[45] A very curious instance of the pursuit of a law completely empirical into an extreme case is to be found in Newton’s rule for the dilatation of his coloured rings seen between glasses at great obliquities. Optics, book ii. part i. obs. 7.

[46] See Phil. Trans. 1819.

[47] “When we are told that Saturn moves in his orbit more than 22,000 miles an hour, we fancy the motion to be swift; but when we find that he is more than three hours moving his own diameter, we must then think it, as it really is, slow.” Thirty Letters on various Subjects, by William Jackson, 1795.

[48] Thomson’s First Principles of Chemistry.

[49] There seems no doubt, however, that an achromatic telescope had been constructed by a private amateur, a Mr. Hall, some time before either Euler or Dollond ever thought of it.

[50] We allude to the recently invented achromatic combinations of Messrs. Barlow and Rogers, and the dense glasses of which Mr. Faraday has recently explained the manufacture in a memoir full of the most beautiful examples of delicate and successful chemical manipulation, and which promise to give rise to a new era in optical practice, by which the next generation at least may benefit. See Phil. Trans. 1830.

[51] Alphonso of Castile, 1252.

[52] Jackson, Letters on Various Subjects, &c.

[53] Thomson’s First Principles of Chemistry, Introduction.

[54] The progress of astronomical discovery has since shown that this law cannot be relied on (1851).

[55] Novum Organum, part ii. table 2. (24), (30), &c. on the form or nature of heat.

[56] We will mention one which we do not remember to have seen noticed elsewhere in the case of a disturbance of the equilibrium of heat produced by means purely mechanical, and by a process depending entirely on a certain order and sequence of events, and the operation of known causes. Suppose a quantity of air enclosed in a metallic reservoir, of some good conductor of heat, and suddenly compressed by a piston. After giving time for the heat developed by the condensation to be communicated from the air to the metal which will be thereby more or less raised in temperature _above_ the surrounding atmosphere, let the piston be suddenly retracted and the air restored to its original volume in an instant. The whole apparatus is now precisely in its initial situation, as to the disposition of its material parts, and the whole quantity of heat it contains remains unchanged. But it is evident that the distribution of this heat within it is now very different from what it was before; for the air in its sudden expansion cannot re-absorb in an instant of time all the heat it had parted with to the metal: it will, therefore, have a temperature _below_ that of the general atmosphere, while the metal yet retains one above it. Thus, a subversion of the equilibrium of temperature has been _bonâ fide_ effected. Heat has been driven from the air into the metal, while every thing else remains unchanged.

We have here a means by which, it is evident, heat may be obtained, to any extent, from the air, without fuel. For if, in place of withdrawing the piston and letting the _same_ air expand, within the reservoir, it be allowed to escape so suddenly as not to re-absorb the heat given off, and fresh air be then admitted and the process repeated, any quantity of air may thus be _drained_ of its heat.

[57] See Phil. Trans. 1824.

[58] If the brain be an electric pile, constantly in action, it may be conceived to discharge itself at regular intervals, when the tension of the electricity developed reaches a certain point, along the nerves which communicate with the heart, and thus to excite the pulsations of that organ. This idea is forcibly suggested by a view of that elegant apparatus, the dry pile of Deluc; in which the successive accumulations of electricity are carried off by a suspended ball, which is kept by the discharges in a state of regular pulsation for any length of time. We have witnessed the action of such a pile maintained in this way for whole years in the study of the above-named eminent philosopher. The same idea of the cause of the pulsation of the heart appears to have occurred to Dr. Arnott; and is mentioned in his useful and excellent work on physics, to which however, we are not indebted for the suggestion, it having occurred to us independently many years ago.

[59] See a description of a contrivance of this kind by Dr. Young, Lectures, vol. i. p. 191.

[60] Boyle’s Works, folio, vol. iii. Essay x. p. 185.

[61] Jackson, The Four Ages, p. 52. London: Cadell and Davies, 1798. 8vo.

[62] Jackson, The Four Ages, p. 90.

Transcriber’s Notes

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