WHEN he entered the University of Edinburgh, James Clerk Maxwell still occasioned some concern to the more conventional amongst his friends by the originality and simplicity of his ways. His replies in ordinary conversation were indirect and enigmatical, often uttered with hesitation and in a monotonous key.[109] While extremely neat in his person, he had a rooted objection to the vanities of starch and gloves. He had a pious horror of destroying anything—even a scrap of writing paper. He preferred travelling by the third class in railway journeys, saying he liked a hard seat. When at table he often seemed abstracted from what was going on, being absorbed in observing the effects of refracted light in the finger-glasses, or in trying some experiment with his eyes—seeing round a corner, making invisible stereoscopes, and the like. Miss Cay used to call his attention by crying, “Jamsie, you’re in a prop.”[110] He never tasted wine; and he spoke to gentle and simple in exactly the same tone. On the other hand, his teachers—Forbes above all—had formed the highest opinion[111] of his intellectual originality and force; and a few experienced observers, in watching his devotion to his father, began to have some inkling of his heroic singleness of heart. To his college companions, whom he could now select at will, his quaint humour was an endless delight. His chief associates, after I went to the University of Glasgow, were my brother, Robert Campbell (still at the Academy), P. G. Tait, and Allan Stewart.[112] Tait went to Peterhouse, Cambridge, in 1848, after one session of the University of Edinburgh; Stewart to the same College in 1849; Maxwell did not go up until 1850.
These three years—November 1847 to October 1850—were impartially divided between Edinburgh and Glenlair. He was working under but slight pressure, and his originality had the freest play. His studies were multifarious, but the subjects on which his thoughts were most concentrated during these years were—1. Polarised light, the stereoscope, etc.; 2. Galvanism; 3. Rolling curves; 4. Compression of solids. That he early felt the necessity of imposing a method on himself will appear from the letters. His paper on Rolling Curves was read before the Edinburgh Royal Society on February 19th, 1849, by Professor Kelland (for it was not thought proper for a boy in a round jacket to mount the rostrum there); that on the Equilibrium of Elastic Solids in the spring of 1850.
With regard to his class studies, it appears that he attended Forbes for two sessions as a regular student, and occasionally as an amateur student in his third year; Kelland for two sessions; and Sir W. Hamilton for two. In his third session, while partially attending Forbes, he was a regular student in the Classes of Chemistry (Professor Gregory), Practical Chemistry (Mr. Kemp), and Moral Philosophy (Professor Wilson).
Mr. Macfarlan of Lenzie, in the letter already quoted, says:—“He was in the Natural Philosophy Class, Edinburgh University, the year before I was, and was spoken of by Forbes and his fellow-students as a discoverer in Natural Philosophy, and a very original worker in Mathematics.”
All scientific theories had an interest for him. It was at some time during these years that in a walk towards Arthur’s Seat he discoursed to me of Owen’s hypothesis of types of creation, not only with complete command of Owen’s terminology, but with far-reaching views of the questions to which the theory led. On the same occasion he made some characteristic remarks on the importance of cultivating the senses, adding that he regarded dulness in that respect as a bad sign of any man.
The lectures in Mental Philosophy, which were a prominent element in the Scottish University curriculum, interested him greatly; and from Sir William Hamilton especially he received an impulse which never lost its effect. Though only sixteen when he entered the Logic Class, he worked hard for it, as his letters show; and from the Class of Metaphysics, which he attended in the following year, his mind gained many lasting impressions.[113] His boundless curiosity was fed by the Professor’s inexhaustible learning; his geometrical imagination predisposed him to accept the doctrine of “natural realism;” while his mystical tendency was soothed by the distinction between Knowledge and Belief. The doctrine of a muscular sense gave promise of a rational analysis of the active powers. However strange it may appear that a born mathematician should have been thus influenced by the enemy of mathematics, the fact is indisputable that in his frequent excursions into the region of speculative thought, the ideas received from Sir William Hamilton were his habitual vantage-ground; the great difference being, that while Sir William remained for the most part within the sphere of Abstract Logic, Maxwell ever sought to bring each “concept” to the test of fact. Sir William in turn took a genial interest in his pupil, who was indeed the nephew of an old friend—Sheriff Cay having at one-time been a constant companion and firm ally of Sir William’s.[114] This is perhaps the most striking example of the effect produced by Sir William Hamilton on powerful young minds,—an effect which, unless the best metaphysicians of the subsequent age are mistaken, must have been out of all proportion to the independent value of his philosophy.
It was impossible that young Maxwell should listen to speculations about the first principles of things,—speculations, too, which, like all the Scottish philosophy, turned largely on the reality of the external world,—without eagerly working out each problem for himself. Besides various exercises done by him for the Logic Class, and, like all his youthful work, preserved by him with pious care, there is one which seems to have attracted special attention, and was found by Professor Baynes, when he came to assist Sir William, in the Professor's private drawer. This is so significant, and is so closely related to Maxwell's after studies, as to deserve insertion here.
On the Properties of Matter.
These properties are all relative to the three abstract entities connected with matter, namely, space, time, and force.
1. Since matter must be in some part of space, and in one part only at a time, it possesses the property of locality or position.
2. But matter has not only position but magnitude; this property is called extension.
3. And since it is not infinite it must have bounds, and therefore it must possess figure.
These three properties belong both to matter and to imaginary geometrical figures, and may be called the geometric properties of matter. The following properties do not necessarily belong to geometric figures.
4. No part of space can contain at the same time more than one body, or no two bodies can coexist in the same space; this property is called impenetrability. It was thought by some that the converse of this was true, and that there was no part of space not filled with matter. If there be a vacuum, said they, that is empty space, it must be either a substance or an accident.
If a substance it must be created or uncreated.
If created it may be destroyed, while matter remains as it was, and thus length, breadth and thickness would be destroyed while the bodies remain at the same distance.
If uncreated, we are led into impiety.
If we say it is an accident, those who deny a vacuum challenge us to define it, and say that length, breadth and thickness belong exclusively to matter.
This is not true, for they belong also to geometric figures, which are forms of thought and not of matter; therefore the atomists maintain that empty space is an accident, and has not only a possible but a real existence, and that there is more space empty than full. This has been well stated by Lucretius.
5. Since there is a vacuum, motion is possible; therefore we have a fifth property of matter called mobility.
And the impossibility of a body changing its state of motion or rest without some external force is called inertia.
Of forces acting between two particles of matter there are several kinds.
The first kind is independent of the quality of the particles, and depends solely on their masses and their mutual distance. Of this kind is the attraction of gravitation and that repulsion which exists between the particles of matter which prevents any two from coming into contact.
The second kind depends on the quality of the particles; of this kind are the attractions of magnetism, electricity, and chemical affinity, which are all convertible into one another and affect all bodies.
The third kind acts between the particles of the same body, and tends to keep them at a certain distance from one another and in a certain configuration.
When this force is repulsive and inversely as the distance, the body is called gaseous.
When it does not follow this law there are two cases.
There may be a force tending to preserve the figure of the body or not.
When this force vanishes the body is a liquid.
When it exists the body is solid.
If it is small the body is soft; if great it is hard.
If it recovers its figure it is elastic; if not it is inelastic.
The forces in this third division depend almost entirely on heat.
The properties of bodies relative to heat and light are—
Transmission, Reflection, and Destruction,
and in the case of light these may be different for the three kinds of light, so that the properties of colour are—
Quality, Purity, and Integrity; or
Hue, Tint, and Shade.
We come next to consider what properties of bodies may be perceived by the senses.
Now the only thing which can be directly perceived by the senses is Force, to which may be reduced heat, light, electricity, sound, and all the things which can be perceived by any sense.
In the sense of sight we perceive at the same time two spheres covered with different colours and shades. The pictures on these two spheres have a general resemblance, but are not exactly the same; and from a comparison of the two spheres we learn, by a kind of intuitive geometry, the position of external objects in three dimensions.
Thus, the object of the sense of sight is the impression made on the different parts of the retina by three kinds of light. By this sense we obtain the greater part of our practical knowledge of locality, extension, and figure as properties of bodies, and we actually perceive colour and angular dimension.
And if we take time into account (as we must always do, for no sense is instantaneous), we perceive relative angular motion.
By the sense of hearing we perceive the intensity, rapidity, and quality of the vibrations of the surrounding medium.
By taste and smell we perceive the effects which liquids and aeriform bodies have on the nerves.
By touch we become acquainted with many conditions and qualities of bodies.
1. The actual dimensions of solid bodies in three dimensions, as compared with the dimensions of our own bodies.
2. The nature of the surface; its roughness or smoothness.
3. The state of the body with reference to heat.
To this is to be referred the sensation of wetness and dryness, on account of the close contact which fluids have with the skin.
By means of touch, combined with pressure and motion, we perceive—
1. Hardness and softness, comprehending elasticity, friability, tenacity, flexibility, rigidity, fluidity, etc.
2. Friction, vibration, weight, motion, and the like.
The sensations of hunger and thirst, fatigue, and many others, have no relation to the properties of bodies.
In connection with his logical studies it should be mentioned that Professor Boole’s attempt, made about this time, towards giving to logical forms a mathematical expression,[116] had naturally strong attractions for Clerk Maxwell.
The metaphysical writers who had received most of his attention before going to Cambridge were Descartes and Leibniz. He knew Hobbes well also, but chiefly on the ethical side.
“When, in his address to Section A of the British Association at the Liverpool meeting in 1870, Maxwell spoke of the barren metaphysics of past ages, he knew the full force of his own words. And he certainly felt that his psychological studies had given him a distinct advantage in conceiving rightly the functions of the eye.
His grasp of Moral Philosophy at the age of nineteen,—when he had been stimulated to precise thought on the subject by listening to the vague harangues of Professor Wilson (Christopher North),—appears in some of his letters, and reveals an aspect of his genius of which too little is known; and one which his subsequent career did not allow him to carry to perfection.
In the third year of his course, as above mentioned, besides attending Professor Wilson’s lectures, he renewed his study of Chemistry under Professor Gregory, to whose laboratory he had unlimited access, and also to some extent continued his attendance on Professor Forbes.
It cannot be said that this period was unfruitful; yet perhaps it is to be regretted that he did not go to Cambridge at least one year earlier. His truly sociable spirit would have been less isolated, he would have gained more command over his own genius, and his powers of expression would have more harmoniously developed. The routine of Cambridge would have been not only more valuable but less irksome to him, and he would have entered sooner and more fully upon the study of mankind, for which he had such large capacity, and opportunities hitherto so limited. He suffered less from isolation than most human beings, and his spirit was deepening all the while; yet the freedom of working by himself during the summer months had manifestly some drawbacks, and the tone of his correspondence shows that he felt the disadvantages of solitude.
Letters, 1847 to 1850—Æt. 16-18.
To Lewis Campbell, Esq.
27 Heriot Row,[117]
Tuesday [16th Novr. 1847].
In Kelland we find the value of expressions in numbers. as fast as we can, the values of the letters being given; light work. In Forbes we do Lever, which is all in Potter; no notes required, only read Pottery ware (light reading). Logic needs long notes. On Monday, Wednesday, Friday, I read Newton’s Fluxions in a sort of way, to know what I am about in doing a prop. There is no time of reading a book better than when you need it, and when you are on the point of finding it out yourself if you were able.
Yours, J. C. M., No. 2.
To the Same.
31 Heriot Row, Novr. 1847.
As you say, sir, I have no idle time. I look over notes and such like till 9.35, then I go to Coll., and I always go one way and cross streets at the same places; then at 10 comes Kelland. He is telling us about arithmetic and how the common rules are the best. At 11 there is Forbes, who has now finished introduction and properties of bodies, and is beginning Mechanics in earnest. Then at 12, if it is fine, I perambulate the Meadows; if not, I go to the Library and do references. At 1 go to Logic. Sir W. reads the first one half of his lecture, and commits the rest to his man, but reserves to himself the right of making remarks. To-day was examination day, and there was no lecture. At 2 I go home and receive interim aliment, and do the needful in the way of business. Then I extend notes, and read text-books, which are Kelland’s Algebra and Potter’s Mechanics. The latter is very trigonometrical, but not deep; and the Trig, is not needed. I intend to read a few Greek and Latin beside. What books are you doing? ... In Logic we sit in seats lettered according to name, and Sir W. takes and puts his hand into a jam pig[118] full of metal letters (very classical), and pulls one out and examines the bench of the letter. The Logic lectures are far the most solid and take most notes.
Before I left home I found out a prop for Tait (P. G.); but he will not do it. It is “to find the algebraical equation to a curve which is to be placed with its axis vertical, and a heavy body is to be put on any part of the curve, as on an inclined plane, and the horizontal component of the force, by which it is actuated, is to vary as the normal n Superscript th power of the perpendicular upon the axis.”
To the Same.
Glenlair, 26th April 1848.
... On Saturday, the natural philosophers ran up Arthur’s Seat with the barometer. The Professor set it up at the top and let us pant at it till it ran down with drops. He did not set it straight, and made the hill grow fifty feet; but we got it down again.
We came here on Wednesday by Caledonian. I intend to open my classes next week after the business is over. I have been reading Xenophon's Memorabilia after breakfast; also a French collection book. This from 9 to 11. Then a game of the Devil, of whom there is a duality and a quaternity of sticks, so that I can play either conjunctly or severally. I can jump over him and bring him round without leaving go the sticks. I can also keep him up behind me.
Then I go in again to science, of which I have only just got the books by the carrier. Hitherto I have done a prop on the slate on polarised light. Of props I have done several.
1. Found the equation to a square.
2. The curve which Sir David Brewster sees when he squints at a wall.
3. A property of the parabola....
4. The same of the Ellipse and Hyperbola....
I can polarise light now by reflection or refraction in 4 ways, and get beautiful but evanescent figures in plate glass by heating its edge. I have not yet unannealed any glass....
I don’t understand how you mug[119] straight on. I suit my muggery to my temper that day. When I am deep I read Xenophon’s defence of normal upper Sigma omega kappa; when not I read normal upper Sigma omega kappa’s witty dialogues. If I do not do this, I always find myself reading Greek, that is, reading the words with all their contractions, as a Jew reads Hebrew. I get on very rapidly; but know nothing about the meaning, and do not even know but that I am really translating.
Please to write about your Prizes at College, and about coming here to mug? You must learn the D——1.
Tatties is planting.—Yours, etc.
To the Same.
Glenlair, 5/6 July 1848.
I was much glad of your letter, and will be thankful for a repetition. I understand better about your not coming. I have regularly set up shop now above the wash-house at the gate, in a garret.[120] I have an old door set on two barrels, and two chairs, of which one is safe, and a skylight above, which will slide up and down.
On the door (or table), there is a lot of howls, jugs, plates, jam pigs,[121] etc., containing water, salt, soda, sulphuric acid, blue vitriol, plumbago ore; also broken glass, iron, and copper wire, copper and zinc plate, bees’ wax, sealing wax, clay, rosin, charcoal, a lens, a Smee’s Galvanic apparatus, and a countless variety of little beetles, spiders, and wood lice, which fall into the different liquids and poison themselves. I intend to get up some more galvanism in jam pigs; but I must first copper the interiors of the pigs, so I am experimenting on the best methods of electrotyping. So I am making copper seals with the device of a beetle. First, I thought a beetle was a good conductor, so I embedded one in wax (not at all cruel, because I slew him in boiling water in which he never kicked), leaving his back out; but he would not do. Then I took a cast of him in sealing wax, and pressed wax into the hollow, and black-leaded it with a brush; but neither would that do. So at last I took my fingers and rubbed it, which I find the best way to use the black lead. Then it coppered famously. I melt out the wax with the lens, that being the cleanest way of getting a strong heat, so I do most things with it that need heat. To-day I astonished the natives as follows. I took a crystal of blue vitriol and put the lens to it, and so drove off the water, leaving a white powder. Then I did the same to some washing soda, and mixed the two white powders together; and made a small native spit on them, which turned them green[122] by a mutual exchange, thus:—1. Sulphate of copper and carbonate of soda. 2. Sulphate of soda and carbonate of copper (blue or green).
With regard to electro-magnetism you may tell Bob that I have not begun the machine he speaks of, being occupied with better plans, one of which is rather down cast, however, because the machine when tried went a bit and stuck; and I did not find out the impediment till I had dreamt over it properly, which I consider the best mode of resolving difficulties of a particular kind, which may be found out by thought, or especially by the laws of association. Thus, you are going along the road with a key in your pocket. You hear a clink behind you, but do not look round, thinking it is nothing particular; when you get home the key is gone; so you dream it all over, and though you have forgotten everything else, you remember the look of the place, but do not remember the locality (that is, as thus, “Near a large thistle on the left side of the road”—nowhere in particular, but so that it can be found). Next day comes a woman from the peats who has found the key in a corresponding place. This is not “believing in dreams,” for the dream did not point out the place by the general locality, but by the lie of the ground.
Please to write and tell how Academy matters go, if they are coming to a head. I am reading Herodotus, Euterpe, having taken the turn; that is to say, that sometimes I can do props, read diff. and Int. Calc., Poisson, Hamilton’s dissertations, etc. Off, then I take back to experiments, history of what you may call it, make up leeway in the newspapers, read Herodotus, and draw the figures of the curves above. O deary, 11 p.m.! Hoping to see you before October.... I defer till to-morrow.
July 6. To-day I have set on to the coppering of the jam pig which I polished yesterday.
I have stuck in the wires better than ever, and it is going on at a great rate, being a rainy day, and the skylight shut and a smell of Hydrogen gas. I have left it for an hour to read Poisson, as I am pleased with him to-day. Sometimes I do not like him, because he pretends to give information as to calculations of sorts, whereas he only tells how it might be done if you were allowed an infinite time to do it in, as well as patience. Of course he never stoops to give a particular example or even class of them. He tells lies about the way people make barometers, etc.
I bathe regularly every day when dry, and try aquatic experiments.
I first made a survey of the pool, and took soundings and marked rocky places well, as the water is so brown that one cannot see one’s knees (pure peat, not mud). People are cutting peats now. So I have found a way of swimming round the pool without knocking knees. The lads[123] are afraid of melting, except one. No one here would touch water if they could help it, because there are two or three eels in the pool, which are thought near as bad as adders.
I took down the clay gun and made a centrifugal pump of it; also tried experiments on sound under water, which is very distinct, and I can understand how fishes can be stunned by knocking a stone.
We sometimes get a rope, which I take hold of at one end, and Bob Fraser the other, standing on the rock; and after a flood, when the water is up, there is sufficient current to keep me up like a kite without striking at all.
The thermometer ranged yesterday from 35° to 69°.
I have made regular figures of 14, 26, 32, 38, 62, and 102 sides of cardboard.
Latest intelligence—Electric Telegraph. This is going so as to make a compass spin very much. I must go to see my pig, as it is an hour and half since I left it; so, sir, am your affib. friend,
James Clerk Maxwell.
To the Same.
Glenlair, 22d Sept 1848.
... When I waken I do so either at 5.45 or 9.15, but I now prefer the early hour, as I take the most of my violent exercise at that time, and thus am saddened down, so that I can do as much still work afterwards as is requisite, whereas if I was to sit still in the morning I would be yawning all day. So I get up and see what kind of day it is, and what field works are to be done; then I catch the pony and bring up the water barrel.[124] This barrel used to be pulled by the men, but Pa caused the road to be gravelled, and so it became horse work to the men, so I proposed the pony; but all the men except the pullers opposed the plan. So I and the children not working brought it up, and silenced vile insinuators. Then I take the dogs out, and then look round the garden for fruit and seeds, and paddle about till breakfast time; after that take up Cicero and see if I can understand him. If so, I read till I stick; if not, I set to Xen. or Herodotus. Then I do props, chiefly on rolling curves, on which subject I have got a great problem divided into Orders, Genera, Species, Varieties, etc.
One curve rolls on another, and with a particular point traces out a third curve on the plane of the first, then the problem is:—Order I. Given any two of these curves, to find the third.
Order II. Given the equation of one and the identity of the other two, find their equation.
Order III. Given all three curves the same, find them. In this last Order I have proved that the equi-angular spiral possesses the property, and that no other curve does. This is the most reproductive curve of any. I think John Bernoulli had it on his tombstone, with the motto Eadem mutata resurgo. There are a great many curious properties of curves connected with rolling. Thus, for example,—
If the curve A when rolled on a straight line produces a curve C, and if the curve A when rolled up on itself produces the curve B, then the curve B when rolled upon the curve C will produce a straight line.
Thus, let the involute of the circle be represented by A, the spiral of Archimedes by B, and the parabola by C, then the proposition is true. Thus the parabola rolled on a straight line traces a Catenary with its focus, an easy way to describe the Catenary. Professor Wallace just missed it in a paper in the Royal Society.
After props come optics, and principally polarised light.
Do you remember our visit to Mr. Nicol? I have got plenty of unannealed glass of different shapes, for I find window glass will do very well made up in bundles. I cut out triangles, squares, etc., with a diamond, about 8 or 9 of a kind, and take them to the kitchen, and put them on a piece of iron in the fire one by one. When the bit is red hot, I drop it into a plate of iron sparks to cool, and so on till all are done. I have got all figures up to nonagons, triangles of all kinds, and irregular chips. I have made a pattern for a tesselated window of unannealed glass in the proper colours, also a delineation of triangles at every principal inclination. We were at Castle-Douglas yesterday, and got crystals of salt Peter, which I have been cutting up into plates to-day, in hopes to see rings. There are very few crystals which are not hollow-hearted or filled up with irregular crystals. I have got a few cross cuts like white hexagon free of irregularities and long [wedge-shaped] cuts for polarising plates. One has to be very cautious in sawing and polishing them, for they are very brittle.
I have got a lucifer match box fitted up for polarising, thus. The rays suffer two reflections at the polarising angle from glasses A and B. Without the lid it does for an analysing plate. Tn the lid there is set a plate of mica, and so one observes the blue sky, and turns the box round till a particular colour appears, and then a line on the lid of the box points to the sun wherever he is. Thus one can find out the time of day without the sun. [Here follow thirteen diagrams of patterns in triangles, squares, pentagons, and hexagons.] These are a few of the figures one sees in unannealed glass.
Pray write soon and tell when, how, and where by, you intend to come, that you may neither on the other hand fall upon us at unawares, nor on the one hand break and not come at all. I suppose when you come I will have to give up all my things of my own devizing, and take Poisson, for the time is short, and I am very nearly unprepared in actual reading, though a great deal more able to read it.
I hope not to write any more letters till you come. I seal with an electrotype of the young of the ephemera. So, sir, I was, etc.
To the Same.
Bannavie, 6th July [1849].
This being a wet night, and I having exhausted my travelling props, set to write to you about what I can recollect of my past history. It is curious that though the remembrance of ploys remains longer than that of home doings, it is not so easily imagined after a short interval.
By imagining is here meant bringing up an accurate image of thoughts, words, and works, and not a mere geographical summary of voyages and travels.
But to the point. Perhaps you remember going with my Uncle John Cay (7th Class), to visit Mr. Nicol in Inverleith Terrace. There we saw polarised light in abundance. I purposed going this session but was prevented. Well, sir, I received from the aforesaid Mr. Cay a “Nicol’s prism,” which Nicol had made and sent him. It is made of calc-spar, so arranged as to separate the ordinary from the extraordinary ray. So I adapted it to a camera lucida, and made charts of the strains in unannealed glass.
I have set up the machine for showing the rings in crystals, which I planned during your visit last year. It answers very well. I also made some experiments on compressed jellies in illustration of my props on that subject The principal one was this:—The jelly is poured while hot into the annular space contained between a paper cylinder and a cork: then, when cold, the cork is twisted round, and the jelly exposed to polarised light, when a transverse cross, x, not +, appears with rings as the inverse square of the radius, all which is fully verified. Hip! etc. Q.E.D.
But to make an abrupt transcision,[125] as Forbes says, we set off to Glasgow on Monday 2d; to Inverary on 3d; to Oban by Loch Awe on 4th; round Mull, by Staffa and Iona, on (5th), and here on 6th. To-morrow we intend to get to Inverness and rest there. On Monday perhaps? to the land of Beulah, and afterwards back by Caledon. Canal to Crinan Canal, and so to Arran, thence to Ardrossan, and then home. It is possible that you may get a more full account of all these things (if agreeable), when I fall in with a pen that will spell; my present instrument partakes of the nature of skates, and I can hardly steer it.
There is a beautiful base here for measuring the height, etc., of Ben Nevis. It is a straight and level road through a moss for about a mile that leads from the inn right to the summit.
It is proposed to carry up stones and erect a cairn 3 feet high, and thus render it the highest mountain in Scotland.
During the session Prof. Forbes gave as an exercise to describe a cycloid from top of Ben Nevis to Fort William, and slide trees down it. We took an observation of the slide, but found nothing to slide but snow.
I think a body deprived of friction would go to Fort William in a cycloid in 49·6 seconds, and in 81 on an inclined plane. I believe I should have written the greater part of this letter to Allan Stewart, but I know not where he is, so you get it, and may read it or no as you like.
We will be at home between the 15th and 22d of this month, so you may write then, detailing your plans and specifying whether you intend to come north at all between this and November, for we would be glad if either you or Bob would disturb our solitude.
To the Same.
Glenlair, 19th October 1849.
Here is the way to dissolve any given historical event in a mythical solution, and then precipitate the seminal ideas in their primitive form. It is from Theodore Parker, an American, and treats of the declaration of American Independence. “The story of the Declaration of Independence is liable to many objections if we examine it à la mode Strauss. The Congress was held at a mythical town, whose very name is suspicious,—Philadelphia, brotherly love. The date is suspicious: it was the fourth day of the fourth month (reckoning from April, as it is probable that the Heraclidae and Scandinavians, possible that the Americans, and certain that the Ebrews, did). Now 4 was a sacred number among Americans: the President was chosen for 4 years, 4 departments of affairs, 4 political powers, etc. The year also is suspicious. 1776 is but an ingeni[ous]? combination of the sacred number, thus—
| 444 |
| 4 |
| 1776 |
Still further, the declaration is metaphysical and presupposes an acquaintance with the transcendental function on the part of the American people. Now the Kritik of Pure Reason was not yet published,” etc.
This is the likeness of a SKEW SCREW SURFACE.
To the Same.
October 1849.
Since last letter, I have made some pairs of diagrams representing solid figures and curves drawn in space; of these pictures one is seen with each eye by means of mirrors, thus....
This is Wheatstone’s Stereoscope, which Sir David Brewster has taken up of late with much violence at the Brightish Association. (The violence consists in making two lenses out of one by breaking it). (See Report). Last winter he exhibited at the Scottish Society of Arts Calotype pictures of the statue of Ariadne and the beast seen from two stations, which, when viewed properly, appeared very solid.
Since then I have been doing practical props on compression, and writing out the same that there may be no mistake. The nicest cases are those of spheres and cylinders. I have got an expression for the hardness of a cricket ball made of case and stuffing. I have also the equations for a spherical cavity in an infinite solid, and this prop: Given that the polarised colour of any part of a cylinder of unannealed glass is equal to the square of the distance from the centre (as determined by observation), to find—1st, the state of strain at each point; 2d, the temperature of each.
I have got an observation of the latitude just now with a saucer of treacle, but it is very windy.
Pray excuse this wickedly perplexed letter as an effect of the paucity of our communications. If you would sharpen me a little it would be acceptable, but when there is nobody to speak to one [loses] the gift of speech....
To the Same.
31 Heriot Row, Edinburgh, N.B., Monday, Nov. 5, 1849.
I go to Gregory to Chemistry at 10, Morale Phil, at 12, and Pract. Chem. at 13, finishing at 14, unless perhaps I take an hour at Practical Mechanics at the School of Arts. I do not go to Sir W. H. logic, seeing I was there before. Langhorne has got your Buchananic notes. Why do you think that I can endure nothing but Mathematics and Logic, the only things I have plenty of? and why do you presuppose my acquaintance with your preceptors, professors, tutors,[126] etc.? ...
I don’t wonder at your failing to take interest in the exponential theorem, seeing I dislike it, although I know the use and meaning of it. But I never would have, unless Kelland had explained it....
In your next letter you may give an abstract of Aristotle’s Rhet., for I do not attend Aytoun, and so I know not what Rhet. is. I know Logic only by Reid's account of it. I will tell you about Wilson’s Moral Philosophy, provided always you want to know, and signify your desire.
To the Same.
[Edin] 14th March 1850.
As I am otherwise engaged, I take this opportunity of provoking you to write a letter or two. I have begun to write Elastic Equilibrium, and I find that I must write you a letter in order at least, indeed,[127] to serve on the one hand as an excuse to myself for sticking up, and on the other hand as a sluice for all the nonsense which I would have written. I therefore propose to divide this letter as follows:—My say naturally breaks up into—1. Education; 2. Notions; 3. Hearsay.
1. Education—Public.
10-11.—Gregory is on Alloys of Metals just now. Last Saturday I was examined, and asked how I would do if the contents of a stomach were submitted to me to detect arsenic, and I had to go through the whole of the preparatory processes of chopping up the tripes, boiling with potash, filtering, boiling with upper H upper C upper L and upper K upper O upper C upper L normal upper O 5, all which Kemp the Practical says are useless and detrimental processes, invented by chemists who want something to do. 11-12.—Prof. Forbes is on Sound and Light day about, as Bob well knows, and can tell you if he chooses. He (B. C.) has written an essay on Probabilities, with very grand props in it; everything original, but no signs of reading, I guess. It was all written in a week. He has despaired of Optics.—12-1. Wilson, after having fully explained his own opinions, has proceeded to those of other great men: Plato, Aristotle, Stoics, Epicureans. He shows that Plato’s proof of the immortality of the soul, from its immateriality, if it be a proof, proves its pre-existence, the immortality of beasts and vegetables, and why not transmigration? (Do you remember how Raphael tells Adam about meats and drinks in Paradise Lost?) (Greek Iambics, if you please.) He quarrels with Aristotle’s doctrine of the Golden Mean,—“a virtue is the mean between two vices,”—not properly understanding the saying. He chooses to consider it as a pocket rule to find virtue, which it is not meant to be, but an apophthegm or maxim, or dark saying, signifying that as a hill falls away on both sides of the top, so a virtue at its maximum declines by excess or defect (not of virtue but) of some variable quantity at the disposal of the will Thus, let it be a virtue to give alms with your own money, then it is a greater virtue to pay one’s debts to the full. Now, a man has so much money: the more alms he gives up to a certain point, the more virtue. As soon as it becomes impossible to pay debts, the virtue of solvency decreases faster than that of alms-giving increases, so that the giving of money to the poor becomes a vice, so that the variable is the sum given away, by excess or defect of which virtue diminishes, say I; so that Wilson garbles Aristotle,—but I bamboozle myself. I say that some things are virtues, others are virtuous or generally lead to virtue. Substitute goods for virtues, and it will be more general: thus, Wisdom, Happiness, Virtue, are goods, and cannot be in excess; but Knowledge, Pleasure, and—what? (please tell me, Is it Propriety, Obedience, or what is it?) lead to the other three, and are not so much goods as tending to good; whereas particular knowledges, pleasures, and obediences may be in excess and lead to evils. I postpone the rest of my observations to my Collection of the Metaphysical principles of Moral Philosophy founded on the three laws of Liberty, Equality, Fraternity, thus expressed:—
1. That which can be done is that which has been done; that is, that the possibility (with respect to the agent) of an action (as simple) depends on the agent having had the sensation of having done it.[128]
2. That which ought to be done is that which (under the given conditions) produces, implies, or tends to the greatest amount of good (an excess or defect in the variables will lessen the good and make evil).
3. Moral actions can be judged of only by the principle of exchange; that is (1), our own actions must be judged by the laws we have made for others; (2), others must be judged by putting ourselves in their place.
22d March.
At Practical Mechanics I have been turning Devils of sorts. For private studies I have been reading Young’s Lectures, Willis’s Principles of Mechanism, Moseley’s Engineering and Mechanics, Dixon on Heat, and Moigno’s Répertoire d'Optique. This last is a very complete analysis of all that has been done in the optical way from Fresnel to the end of 1849, and there is another volume a-coming which will complete the work. There is in it besides common optics all about the other things which accompany light, as heat, chemical action, photographic rays, action on vegetables, etc.
My notions are rather few, as I do not entertain them just now. I have a notion for the torsion of wires and rods, not to be made till the vacation; of experiments on the action of compression on glass, jelly, etc., numerically done up; of papers for the Physico-Mathematical Society (which is to revive in earnest next session!); on the relations of optical and mechanical constants, their desirableness, etc., and suspension-bridges, and catenaries, and elastic curves. Alex. Campbell, Agnew, and I are appointed to read up the subject of periodical shooting stars, and to prepare a list of the phenomena to be observed on the 9th August and 13th November. The Society’s barometer is to be taken up Arthur’s Seat at the end of the session, when Forbes goes up, and All students are invited to attend, so that the existence of the Society may be recognised.
I have notions of reading the whole of Corpus Juris and Pandects in no time at all; but these are getting somewhat dim, as the Cambridge scheme has been howked up from its repose in the regions of abortions, and is as far forward as an inspection of the Cambridge Calendar and a communication with Cantabs.
Mr. Bob is choosing his college. I rejected for him all but Peter’s, Caius, or Trinity Hall, the last being, though legal, not in favour, or lazy, or something. Caius is populous, and is society to itself. Peter’s is select, and knows the University. Please give me some notions on these things, both for Bob and me. I postpone my answer to you about the Gorham business till another time, when also I shall have read Waterland on Regeneration, which is with Mrs. Morrieson, and some Pusey books I know. In the meantime I admire the Judgement as a composition of great art and ingenuity.
What cross influences had delayed his entrance at Cambridge may be guessed at, but cannot be clearly known. Mr. Clerk Maxwell was always slow in making up his mind, and the habit of inertia had grown upon him. There had been a lingering expectation, to which James alludes in the preceding letter, that he would follow his father's profession, and become a member of the Scottish Bar. And although he himself felt, as he told me at the time, that it was “another kind of laws” he was called upon to study, the practical result of this conviction was slow in asserting itself. The fact that in going to Cambridge he decided against the profession which his friends had destined for him made the step a more serious one than it might have otherwise been. The close and constant intercourse between father and son made the parting more difficult. James’s delicate health[129] would count heavily amongst the reasons contra, and certain floating prejudices about the “dangers of the English universities,” Puseyism, infidelity, etc., had then considerable hold, especially on the Presbyterian mind. James himself was patient, and had hitherto decided nothing for himself. Only when Tait and Allan Stewart were already at Cambridge, my brother Robert destined for it, and myself at Oxford, his own voice was added to those which had long been urging the claims of Cambridge,[130] and then they prevailed. There had been searchings of heart on the subject as early as April 1849, when the following entries occur in the Diary:—