CHAPTER VI.

CAMBRIDGE--THE CAVENDISH LABORATORY.

But the laboratory was not yet built. A Syndicate, of which Maxwell was a member, was appointed to consider the question of a site, to take professional advice, and to obtain plans and estimates. Professor Maxwell and Mr. Trotter visited various laboratories at home and abroad for the purpose of ascertaining the best arrangements. Mr. W. M. Fawcett was appointed architect; the tender of Mr. John Loveday, of Kebworth, for the building at a cost of £8,450, exclusive of gas, water, and heating, was accepted in March, 1872, and the building[38] was begun during the summer.

In the meantime Maxwell began to lecture, finding a home where he could.

“Lectures begin 24th,” he writes from Glenlair, October 19th, 1872. “Laboratory rising, I hear, but I have no place to erect my chair, but move about like the cuckoo, depositing my notions in the Chemical Lecture-room 1st term; in the Botanical in Lent, and in Comparative Anatomy in Easter.”

It was not till June, 1874, that the building was complete, and on the 16th the Chancellor formally presented his gift of the Cavendish Laboratory to the University. In the correspondence previous to this time it was spoken of as the Devonshire Laboratory. The name Cavendish commemorated the work of the great physicist of a century earlier, whose writings Maxwell was shortly to edit, as well as the generosity of the Chancellor.

In their letter of thanks to the Duke of Devonshire the University write:--

“Unde vero conventius poterat illis artibus succurri quam e tua domo quæ in ipsis jam pridem inclaruerat. Notum est Henricum Cavendish quem secutus est Coulombius primum ita docuisse, quæ sit vis electrica ut eam numerorum modulis illustraret; adhibitis rationibus quas hodie veras esse constat.” And they suggest the name as suitable for the building. To this the Chancellor replied, after referring to the work of Henry Cavendish: “Quod pono in officinâ ipsâ nuncupandâ nomen ejus commemorare dignati sitis, id grato animo accepi.”

The building had cost far more than the original estimate, but the Chancellor’s generosity was not limited, and on July 21st, 1874, he wrote to the Vice-Chancellor:--

“It is my wish to provide all instruments for the Cavendish Laboratory which Professor Maxwell may consider to be immediately required, either in his lectures or otherwise.”

Maxwell prepared a list, but explained while doing it that time and thought were necessary to secure the best form of instruments; and he continues, writing to the Vice-Chancellor: “I think the Duke fully understood from what I said to him that to furnish the Laboratory will be a matter of several years’ duration. I shall consider myself, however,” he says, “at liberty to contribute to the Laboratory any instruments which I have had constructed in former years, and which may be found still useful, and also from time to time to procure others for special researches.”

In 1877 in his annual report Professor Maxwell announced that the Chancellor[39] had now “completed his gift to the University by furnishing the Cavendish Laboratory with apparatus suited to the present state of science.”

The stock of apparatus, however, was still small, although Maxwell in the most generous manner himself spent large sums in adding to it; for the Professor was most particular in procuring only expensive instruments by the best makers, with such additional improvements as he could himself suggest.

In March, 1874, a Demonstratorship of Physics had been established, and Mr. Garnett of St. John’s College was appointed.

Work began in the laboratory in October, 1874. At first the number of students was small. Only seventeen names appear in the Natural Sciences Tripos[40] list for 1874, and few of those did Physics.

The fear alluded to by the Professor in his introductory lecture, that men reading for the Mathematical Tripos would not find time for attendance at the laboratory, was justified. One of the weaknesses of our Cambridge plan has been the divorce between Mathematics and experimental work, encouraged by our system of examinations. Experimental knowledge is supposed not to be needed for the Mathematical Tripos; the Mathematics permitted in the Natural Sciences Tripos are very simple; thus it came about that few men while reading for the Mathematical Tripos attended the laboratory, and this unfortunate result was intensified by the action of the University in 1877–78, when the regulations for the Mathematical Tripos were again altered.[41]

Still there were pupils eager and willing to work, though they were chiefly men who had already taken their B.A. degree, and who wished to continue Physical reading and research, even though it involved “a considerable amount of dull labour not altogether attractive.” My own work there began in 1876, and it may be interesting if I recall my reminiscences of that time.

The first experiments I can recollect related to the measurement of electrical resistance. I well remember Maxwell explaining the principle of Wheatstone’s bridge, and my own wish at the time that I had come to the laboratory before the Tripos, instead of afterwards. Lord Rayleigh had, during the examination, set an easy question which I failed to do for want of some slight experimental knowledge, and the first few words of Maxwell’s talk showed me the solution.

I did not attend his lectures regularly--they were given, I think, at an hour which I was obliged to devote to teaching; besides, there was his book, the “Electricity and Magnetism,” into which I had just dipped before the Tripos, to work at.

Chrystal and Saunder were then busy at their verification of Ohm’s law. They were using a number of the Thomson form of tray Daniell’s cells, and Maxwell was anxious for tests of various kinds to be made on these cells; these I undertook, and spent some time over various simple measurements on them. He then set me to work at some of the properties of a stratified dielectric, consisting, if I remember rightly, of sheets of paraffin paper and mica. By this means I became acquainted with various pieces of apparatus. There were no regular classes and no set drill of demonstrations arranged for examination purposes; these came later. In Maxwell’s time those who wished to work had the use of the laboratory and assistance and help from him, but they were left pretty much to themselves to find out about the apparatus and the best methods of using it.

Rather later than this Schuster came and did some of his spectroscope work. J. E. H. Gordon was busy with the preliminary observations for his determination of Verdet’s constant, and Niven had various electrical experiments on hand; while Fleming was at work on the B. A. resistance coils.

My own tastes lay in the direction of optics. Maxwell was anxious that I should investigate the properties of certain crystals. I think they were the chlorate of potash crystals, about which Stokes and Rayleigh have since written; but these crystals were to be grown, a slow process which would, he supposed, take years; and as I wished to produce a dissertation for the Trinity Fellowship examination in 1877, that work had to be laid aside.

Eventually I selected as a subject the form of the wave surface in a biaxial crystal, and set to work in a room assigned to me. The Professor used to come in on most days to see how I was getting on. Generally he brought his dog, which sometimes was shut up in the next room while he went to college. Dogs were not allowed in college, and Maxwell had an amusing way of describing how Toby once wandered into Trinity, and by some doggish instinct discovered immediately, to his intense amazement, that he was in a place where no dogs had been since the college was. Toby was not always quiet in his master’s absence, and his presence in the next room was somewhat disturbing.

When difficulties occurred Maxwell was always ready to listen. Often the answer did not come at once, but it always did come after a little time. I remember one day, when I was in a serious dilemma, I told him my long tale, and he said:--

“Well, Chrystal has been talking to me, and Garnett and Schuster have been asking questions, and all this has formed a good thick crust round my brain. What you have said will take some time to soak through, but we will see about it.” In a few days he came back with--“I have been thinking over what you said the other day, and if you do so-and-so it will be all right.”

My dissertation was referred to him, and on the day of the election, when returning to Cambridge for the admission, I met him at Bletchley station, and well remember his kind congratulations and words of warm encouragement.

For the next year and a half I was working regularly at the laboratory and saw him almost daily during term time.

Of these last years there really is but little to tell. His own scientific work went on. The “Electricity and Magnetism” was written mostly at Glenlair. About the time of his return to Cambridge, in October, 1872, he writes[42] to Lewis Campbell:--

“I am continually engaged in stirring up the Clarendon Press, but they have been tolerably regular for two months. I find nine sheets in thirteen weeks is their average. Tait gives me great help in detecting absurdities. I am getting converted to quaternions, and have put some in my book.”

The book was published in 1873. The Text-book of Heat was written during the same period, while “Matter and Motion,” “a small book on a great subject,” was published in 1876.

In 1873 and 1874 he was one of the examiners for the Natural Sciences Tripos, and in 1873 he was the first additional examiner for the Mathematical Tripos, in accordance with the scheme which he had done so much to promote in 1868.

Many of his shorter papers were written about the same time. The ninth edition of the _Encyclopædia Britannica_ was being published, and Professor Baynes had enlisted his aid in the work. The articles “Atom,” “Attraction,” “Capillary Action,” “Constitution of Bodies,” “Diffusion,” “Ether,” “Faraday,” and others are by him.

He also wrote a number of papers for _Nature_. Some of these are reviews of books or accounts of scientific men, such as the notices of Faraday and Helmholtz, which appeared with their portraits; others again are original contributions to science. Among the latter many have reference to the molecular constitution of bodies. Two lectures--the first on “Molecules,” delivered before the British Association at Bradford in 1873; the second on the “Dynamical Evidence of the Molecular Constitution of Bodies,” delivered before the Chemical Society in 1875--were of special importance. The closing sentences of the first lecture have been often quoted. They run as follow:--

“In the heavens we discover by their light, and by their light alone, stars so distant from each other that no material thing can ever have passed from one to another; and yet this light, which is to us the sole evidence of the existence of these distant worlds, tells us also that each of them is built up of molecules of the same kinds as those which we find on earth. A molecule of hydrogen, for example, whether in Sirius or in Arcturus, executes its vibrations in precisely the same time.

“Each molecule therefore throughout the universe bears impressed upon it the stamp of a metric system, as distinctly as does the metre of the Archives at Paris, or the double royal cubit of the temple of Karnac.

“No theory of evolution can be formed to account for the similarity of molecules, for evolution necessarily implies continuous change, and the molecule is incapable of growth or decay, of generation or destruction.

“None of the processes of Nature, since the time when Nature began, have produced the slightest difference in the properties of any molecule. We are therefore unable to ascribe either the existence of the molecules or the identity of their properties to any of the causes which we call natural.

“On the other hand, the exact equality of each molecule to all others of the same kind gives it, as Sir John Herschel has well said, the essential character of a manufactured article, and precludes the idea of its being eternal and self-existent.

“Thus we have been led along a strictly scientific path, very near to the point at which Science must stop--not that Science is debarred from studying the internal mechanism of a molecule which she cannot take to pieces any more than from investigating an organism which she cannot put together. But in tracing back the history of matter, Science is arrested when she assures herself, on the one hand, that the molecule has been made, and, on the other, that it has not been made by any of the processes we call natural.

“Science is incompetent to reason upon the creation of matter itself out of nothing. We have reached the utmost limits of our thinking faculties when we have admitted that because matter cannot be eternal and self-existent, it must have been created.

“It is only when we contemplate, not matter in itself, but the form in which it actually exists, that our mind finds something on which it can lay hold.

“That matter, as such, should have certain fundamental properties, that it should exist in space and be capable of motion, that its motion should be persistent, and so on, are truths which may, for anything we know, be of the kind which metaphysicians call necessary. We may use our knowledge of such truths for purposes of deduction, but we have no data for speculating as to their origin.

“But that there should be exactly so much matter and no more in every molecule of hydrogen is a fact of a very different order. We have here a particular distribution of matter--a _collocation_, to use the expression of Dr. Chalmers, of things which we have no difficulty in imagining to have been arranged otherwise.

“The form and dimensions of the orbits of the planets, for instance, are not determined by any law of nature, but depend upon a particular collocation of matter. The same is the case with respect to the size of the earth, from which the standard of what is called the metrical system has been derived. But these astronomical and terrestrial magnitudes are far inferior in scientific importance to that most fundamental of all standards which forms the base of the molecular system. Natural causes, as we know, are at work which tend to modify, if they do not at length destroy, all the arrangements and dimensions of the earth and the whole solar system. But though in the course of ages catastrophes have occurred and may yet occur in the heavens, though ancient systems may be dissolved and new systems evolved out of their ruins, the molecules out of which these systems are built--the foundation stones of the material universe--remain unbroken and unworn. They continue this day as they were created--perfect in number and measure and weight; and from the ineffaceable characters impressed on them we may learn that those aspirations after accuracy in measurement, and justice in action, which we reckon among our noblest attributes as men, are ours because they are essential constituents of the image of Him who in the beginning created, not only the heaven and the earth, but the materials of which heaven and earth consist.”

This was criticised in _Nature_ by Mr. C. J. Munro, and at a later time by Clifford in one of his essays.

Some correspondence with the Bishop of Gloucester and Bristol on the authority for the comparison of molecules to manufactured articles is given by Professor Campbell, and in it Maxwell points out that the latter part of the article “Atom” in the _Encyclopædia_ is intended to meet Mr. Munro’s criticism.

In 1874 the British Association met at Belfast, under the presidency of Tyndall. Maxwell was present, and published afterwards in _Blackwood’s Magazine_ an amusing paraphrase of the president’s address. This, with some other verses written at about the same time, may be quoted here. Professor Campbell has collected a number of verses written by Maxwell at various times, which illustrate in an admirable manner both the grave and the gay side of his character.

BRITISH ASSOCIATION, 1874.

_Notes of the President’s Address._

In the very beginnings of science, the parsons, who managed things then, Being handy with hammer and chisel, made gods in the likeness of men; Till commerce arose, and at length some men of exceptional power Supplanted both demons and gods by the atoms, which last to this hour. Yet they did not abolish the gods, but they sent them well out of the way, With the rarest of nectar to drink, and blue fields of nothing to sway. From nothing comes nothing, they told us--naught happens by chance, but by fate; There is nothing but atoms and void, all else is mere whims out of date! Then why should a man curry favour with beings who cannot exist, To compass some petty promotion in nebulous kingdoms of mist? But not by the rays of the sun, nor the glittering shafts of the day, Must the fear of the gods be dispelled, but by words, and their wonderful play. So treading a path all untrod, the poet-philosopher sings Of the seeds of the mighty world--the first-beginnings of things; How freely he scatters his atoms before the beginning of years; How he clothes them with force as a garment, those small incompressible spheres! Nor yet does he leave them hard-hearted--he dowers them with love and with hate, Like spherical small British Asses in infinitesimal state; Till just as that living Plato, whom foreigners nickname Plateau,[43] Drops oil in his whisky-and-water (for foreigners sweeten it so); Each drop keeps apart from the other, enclosed in a flexible skin, Till touched by the gentle emotion evolved by the prick of a pin: Thus in atoms a simple collision excites a sensational thrill, Evolved through all sorts of emotion, as sense, understanding, and will (For by laying their heads all together, the atoms, as councillors do, May combine to express an opinion to every one of them new). There is nobody here, I should say, has felt true indignation at all, Till an indignation meeting is held in the Ulster Hall; Then gathers the wave of emotion, then noble feelings arise, Till you all pass a resolution which takes every man by surprise. Thus the pure elementary atom, the unit of mass and of thought, By force of mere juxtaposition to life and sensation is brought; So, down through untold generations, transmission of structureless gorms Enables our race to inherit the thoughts of beasts, fishes, and worms. We honour our fathers and mothers, grandfathers and grandmothers too; But how shall we honour the vista of ancestors now in our view? First, then, let us honour the atom, so lively, so wise, and so small; The atomists next let us praise, Epicurus, Lucretius, and all. Let us damn with faint praise Bishop Butler, in whom many atoms combined To form that remarkable structure it pleased him to call--his mind. Last, praise we the noble body to which, for the time, we belong, Ere yet the swift whirl of the atoms has hurried us, ruthless, along, The British Association--like Leviathan worshipped by Hobbes, The incarnation of wisdom, built up of our witless nobs, Which will carry on endless discussions when I, and probably you, Have melted in infinite azure--in English, till all is blue.

MOLECULAR EVOLUTION.

_Belfast, 1874._

At quite uncertain times and places, The atoms left their heavenly path, And by fortuitous embraces Engendered all that being hath. And though they seem to cling together, And form “associations” here, Yet, soon or late, they burst their tether, And through the depths of space career.

So we who sat, oppressed with science, As British Asses, wise and grave, Are now transformed to wild Red Lions,[44] As round our prey we ramp and rave. Thus, by a swift metamorphōsis, Wisdom turns wit, and science joke, Nonsense is incense to our noses, For when Red Lions speak they smoke.

Hail, Nonsense! dry nurse of Red Lions,[45] From thee the wise their wisdom learn; From thee they cull those truths of science, Which into thee again they turn. What combinations of ideas Nonsense alone can wisely form! What sage has half the power that she has, To take the towers of Truth by storm?

Yield, then, ye rules of rigid reason! Dissolve, thou too, too solid sense! Melt into nonsense for a season, Then in some nobler form condense. Soon, all too soon, the chilly morning This flow of soul will crystallise; Then those who Nonsense now are scorning May learn, too late, where wisdom lies.

TO THE COMMITTEE OF THE CAYLEY PORTRAIT FUND.

1874.

O wretched race of men, to space confined! What honour can ye pay to him, whose mind To that which lies beyond hath penetrated? The symbols he hath formed shall sound his praise, And lead him on through unimagined ways To conquests new, in worlds not yet created.

First, ye Determinants! in ordered row And massive column ranged, before him go, To form a phalanx for his safe protection. Ye powers of the _n^{th}_ roots of -1! Around his head in ceaseless[46] cycles run, As unembodied spirits of direction.

And you, ye undevelopable scrolls! Above the host wave your emblazoned rolls, Ruled for the record of his bright inventions. Ye cubic surfaces! by threes and nines Draw round his camp your seven-and-twenty lines-- The seal of Solomon in three dimensions.

March on, symbolic host! with step sublime, Up to the flaming bounds of Space and Time! There pause, until by Dickinson depicted, In two dimensions, we the form may trace Of him whose soul, too large for vulgar space, In _n_ dimensions flourished unrestricted.

IN MEMORY OF EDWARD WILSON,

_Who repented of what was in his mind to write after section._

RIGID BODY (_sings_).

GIN a body meet a body Flyin’ through the air, Gin a body hit a body, Will it fly? and where? Ilka impact has its measure, Ne’er a ane hae I; Yet a’ the lads they measure me, Or, at least, they try.

Gin a body meet a body Altogether free, How they travel afterwards We do not always see. Ilka problem has its method By analytics high; For me, I ken na ane o’ them, But what the waur am I?

Another task, which occupied much time, from 1874 to 1879, was the edition of the works of Henry Cavendish. Cavendish, who was great-uncle to the Chancellor, had published only two electrical papers, but he had left some twenty packets of manuscript on Mathematical and Experimental Electricity. These were placed in Maxwell’s hands in 1874 by the Duke of Devonshire.

Niven, in his preface to the collected papers dealing with this book, writes thus:--

“This work, published in 1879, has had the effect of increasing the reputation of Cavendish, disclosing as it does the unsuspected advances which that acute physicist had made in the Theory of Electricity, especially in the measurement of electrical quantities. The work is enriched by a variety of valuable notes, in which Cavendish’s views and results are examined by the light of modern theory and methods. Especially valuable are the methods applied to the determination of the electrical capacities of conductors and condensers, a subject in which Cavendish himself showed considerable skill both of a mathematical and experimental character.

“The importance of the task undertaken by Maxwell in connection with Cavendish’s papers will be understood from the following extract from his introduction to them:--

“‘It is somewhat difficult to account for the fact that though Cavendish had prepared a complete description of his experiments on the charges of bodies, and had even taken the trouble to write out a fair copy, and though all this seems to have been done before 1774, and he continued to make experiments in electricity till 1781, and lived on till 1810, he kept his manuscript by him and never published it.

“‘Cavendish cared more for investigation than for publication. He would undertake the most laborious researches in order to clear up a difficulty which no one but himself could appreciate or was even aware of, and we cannot doubt that the result of his enquiries, when successful, gave him a certain degree of satisfaction. But it did not excite in him that desire to communicate the discovery to others, which in the case of ordinary men of science generally ensures the publication of their results. How completely these researches of Cavendish remained unknown to other men of science is shown by the external history of electricity.’

“It will probably be thought a matter of some difficulty to place oneself in the position of a physicist of a century ago, and to ascertain the exact bearing of his experiments. But Maxwell entered upon this undertaking with the utmost enthusiasm, and succeeded in identifying himself with Cavendish’s methods. He showed that Cavendish had really anticipated several of the discoveries in electrical science which have been made since his time. Cavendish was the first to form the conception of and to measure Electrostatic Capacity and Specific Inductive Capacity; he also anticipated Ohm’s law.”

During the last years of his life Mrs. Maxwell had a serious and prolonged illness, and Maxwell’s work was much increased by his duties as sick nurse. On one occasion he did not sleep in a bed for three weeks, but conducted his lectures and experiments at the laboratory as usual.

About this time some of those who had been “Apostles” in 1853–57 revived the habit of meeting together for discussion. The club, which included Professors Lightfoot, Hort and Westcott, was christened the “Eranus,” and three of Maxwell’s contributions to it have been preserved and are printed by Professor Campbell.

After the Cavendish papers were finished, Maxwell had more time for his own original researches, and two important papers were published in 1879. The one on “Stresses in Rarefied Gases arising from Inequalities of Temperature” was printed in the Royal Society’s Transactions, and deals with the Theory of the Radiometer; the other on “Boltzmann’s Theorem” appears in the Transactions of the Cambridge Philosophical Society. In the previous year he had delivered the Rede lecture on “The Telephone.” He also began to prepare a second edition of “Electricity and Magnetism.”

His health gave way during the Easter term of 1879; indeed for two years previously he had been troubled with dyspeptic symptoms, but had consulted no one on the subject. He left Cambridge as usual in June, hoping that he would quickly recover at Glenlair, but he grew worse instead. In October he was told by Dr. Sanders of Edinburgh that he had not a month to live. He returned to Cambridge in order to be under the care of Dr. Paget, who was able in some measure to relieve his most severe suffering but the disease, of which his mother had died at the same age, continued its progress, and he died on November 5th. His one care during his last illness was for those whom he left behind. Mrs. Maxwell was an invalid dependent on him for everything, and the thought of her helplessness was the one thing which in these last days troubled him.

A funeral service took place in the chapel at Trinity College, and afterwards his remains were conveyed to Scotland and interred in the family burying-place at Corsock, Kirkcudbright.

A memorial edition of his works was issued by the Cambridge University Press in 1890. A portrait by Lowes Dickinson hangs in the hall of Trinity College, and there is a bust by Boehm in the laboratory.

After his death Mrs. Maxwell gave his scientific library to the Cavendish Laboratory, and on her death she left a sum of about £6,000 to found a scholarship in Physics, to be held at the laboratory.

* * * * *

The preceding pages contain some account of Clerk Maxwell’s life as a man of science. His character had other sides, and any life of him would be incomplete without some brief reference to these. His letters to his wife and to other intimate friends show throughout his life the depth of his religious convictions. The high purpose evidenced in the paper given to the present Dean of Canterbury when leaving Cambridge, animated him continually, and appears from time to time in his writings. The student’s evening hymn, composed in 1853 when still an undergraduate, expresses the same feelings--

Through the creatures Thou hast made Show the brightness of Thy glory, Be eternal truth displayed In their substance transitory, Till green earth and ocean hoary, Massy rock and tender blade, Tell the same unending story, “We are Truth in form arrayed.”

Teach me so Thy works to read That my faith, new strength accruing, May from world to world proceed, Wisdom’s fruitful search pursuing, Till Thy breath my mind imbuing, I proclaim the eternal creed, Oft the glorious theme renewing, God our Lord is God indeed.

His views on the relation of Science to Faith are given in his letter[47] to Bishop Ellicott already referred to--

“But I should be very sorry if an interpretation founded on a most conjectural scientific hypothesis were to get fastened to the text in Genesis, even if by so doing it got rid of the old statement of the commentators which has long ceased to be intelligible. The rate of change of scientific hypothesis is naturally much more rapid than that of Biblical interpretations, so that if an interpretation is founded on such an hypothesis, it may help to keep the hypothesis above ground long after it ought to be buried and forgotten.

“At the same time I think that each individual man should do all he can to impress his own mind with the extent, the order, and the unity of the universe, and should carry these ideas with him as he reads such passages as the 1st chapter of the Epistle to Colossians (_see_ ‘Lightfoot on Colossians,’ p. 182), just as enlarged conceptions of the extent and unity of the world of life may be of service to us in reading Psalm viii., Heb. ii. 6, etc.”

And again in his letter[48] to the secretary of the Victoria Institute giving his reasons for declining to become a member--

“I think men of science as well as other men need to learn from Christ, and I think Christians whose minds are scientific are bound to study science, that their view of the glory of God may be as extensive as their being is capable of. But I think that the results which each man arrives at in his attempts to harmonise his science with his Christianity ought not to be regarded as having any significance except to the man himself, and to him only for a time, and should not receive the stamp of a society.”

Professor Campbell and Mr. Garnett have given us the evidence of those who were with him in his last days, as to the strength of his own faith. On his death bed he said that he had been occupied in trying to gain truth; that it is but little of truth that man can acquire, but it is something to know in whom we have believed.