CHAPTER V.

CAMBRIDGE.--PROFESSOR OF PHYSICS.

During his retirement at Glenlair from 1865 to 1870 Maxwell was

frequently at Cambridge. He examined in the Mathematical Tripos in 1866

and 1867, and again in 1869 and 1870.

The regulations for the Tripos had been in force practically unchanged

since 1848, and it was felt by many that the range of subjects included

was not sufficiently extensive, and that changes were urgently needed

if Cambridge were to retain its position as the centre of mathematical

teaching. Natural Philosophy was mentioned in the Schedule, but Natural

Philosophy included only Dynamics and Astronomy, Hydrostatics and

Physical Optics, with some simple Hydrodynamics and Sound.

The subjects of Heat, Electricity and Magnetism, the Theory of Elastic

Solids and Vibrations, Vortex-Motion in Hydrodynamics, and much else,

were practically new since 1848. Stokes, Thomson, and Maxwell in

England, and Helmholtz in Germany, had created them.

Accordingly in June, 1868, a new plan of examinations was sanctioned

by the Senate to come into force in January, 1873, and these various

subjects were explicitly included.

Mr. Niven, who was one of those examined by Maxwell in 1866, writes in

the preface to the collected works:--

“For some years previous to 1866, when Maxwell returned to

Cambridge as Moderator in the Mathematical Tripos, the studies

in the University had lost touch with the great scientific

movements going on outside her walls. It was said that some

of the subjects most in vogue had but little interest for the

present generation, and loud complaints began to be heard

that while such branches of knowledge as Heat, Electricity,

and Magnetism were left out of the Tripos examination, the

candidates were wasting their time and energy upon mathematical

trifles barren of scientific interest and of practical results.

Into the movement for reform Maxwell entered warmly. By his

questions in 1866, and subsequent years, he infused new life

into the examination; he took an active part in drafting the

new scheme introduced in 1873; but most of all by his writings

he exerted a powerful influence on the younger members of the

University, and was largely instrumental in bringing about the

change which has been now effected.”

But the University possessed no means of teaching these subjects, and a

Syndicate or Committee was appointed, November 25th, 1868, “to consider

the best means of giving instruction to students in Physics, especially

in Heat, Electricity and Magnetism, and the methods of providing

apparatus for this purpose.”

Dr. Cookson, Master of St. Peter’s College, took an active part in the

work of the Syndicate. Professor Stokes, Professor Liveing, Professor

Humphry, Dr. Phear, and Dr. Routh were among the members. Maxwell

himself was in Cambridge that winter, as Examiner for the Tripos, and

his work as Moderator and Examiner in the two previous years had done

much to show the necessity of alterations and to indicate the direction

which changes should take.

The Syndicate reported February 27th, 1869. They called attention to

the Report of the Royal Commission of 1850. The Commissioners had

“prominently urged the importance of cultivating a knowledge of the

great branches of Experimental Physics in the University”; and in

page 118 of their Report, after commending the manner in which the

subject of Physical Optics is studied in the University, and pointing

out that “there is, perhaps, no public institution where it is better

represented or prosecuted with more zeal and success in the way of

original research,” they had stated that “no reason can be assigned

why other great branches of Natural Science should not become equally

objects of attention, or why Cambridge should not become a great school

of physical and experimental, as it is already of mathematical and

classical, instruction.”

And again the Commissioners remark: “In a University so thoroughly

imbued with the mathematical spirit, physical study might be expected

to assume within its precincts its highest and severest tone, be

studied under more abstract forms, with more continual reference to

mathematical laws, and therefore with better hope of bringing them one

by one under the domain of mathematical investigation than elsewhere.”

After calling attention to these statements the Report of the Syndicate

then continues:--

“In the scheme of Examination for Honours in the Mathematical Tripos

approved by Grace of the Senate on the 2nd of June, 1868, Heat,

Electricity and Magnetism, if not introduced for the first time, had a

much greater degree of importance assigned to them than at any previous

period, and these subjects will henceforth demand a corresponding

amount of attention from the candidates for Mathematical Honours. The

Syndicate have limited their attention almost entirely to the question

of providing public instruction in Heat, Electricity and Magnetism.

They recognise the importance and advantage of tutorial instruction in

these subjects in the several colleges, but they are also alive to the

great impulse given to studies of this kind, and to the large amount of

additional training which students may receive through the instruction

of a public Professor, and by knowledge gained in a well-appointed

laboratory.”

“In accordance with these views, and at an early period in their

deliberations, they requested the Professors[34] of the University, who

are engaged in teaching Mathematical and Physical Science, to confer

together upon the present means of teaching Experimental Physics,

especially Heat, Electricity and Magnetism, and to inform them how the

increased requirements of the University in this respect could be met

by them.”

“The Professors, so consulted, favoured the Syndicate with a report

on the subject, which the Syndicate now beg leave to lay before the

Senate. It points out how the requirements of the University might

be “partially met,” but the Professors state distinctly that they

“do not think that they are able to meet the want of an extensive

course of lectures on Physics treated as such, and in great measure

experimentally. As Experimental Physics may fairly be considered

to come within the province of one or more of the above-mentioned

Professors, the Syndicate have considered whether now or at some

future time some arrangement might not be made to secure the effective

teaching of this branch of science, without having resort to the

services of an additional Professor. They are, however, of opinion that

such an arrangement cannot be made at the present time, and that the

exigencies of the case may be best met by founding a new professorship

which shall terminate with the tenure of office of the Professor first

elected. The services of a man of the highest attainments in science,

devoting his life to public teaching as such Professor, and engaged in

original research, would be of incalculable benefit to the University.”

The Report goes on to point out that a laboratory would be necessary,

and also apparatus. It is estimated that £5,000 would cover the cost

of the laboratory, and £1,300 the necessary apparatus. Provision is

also made for a demonstrator and a laboratory assistant, and the Report

closes with a recommendation that a special Syndicate of Finance should

be appointed to consider the means of raising the funds.

The Professors in their Report to the Syndicate point out that teaching

in Experimental Physics is needed for the Mathematical Tripos, the

Natural Sciences Tripos, certain Special examinations, and the first

examination for the degree of M.B. It appeared to them clear that there

was work for a new Professor.

In May, 1869, the Financial Syndicate recommended by the above Report

was appointed “to consider the means of raising the necessary funds for

establishing a professor and demonstrator of Experimental Physics, and

for providing buildings and apparatus required for that department of

science, and further to consider other wants of the University, and the

sources from which those wants may be supplied.”

The Syndicate endeavoured to meet the expenditure by inquiry from the

several Colleges whether they would be willing to make contributions

from their corporate funds, but without success.

“The answers of the Colleges indicated such a want of concurrence

in any proposal to raise contributions from the corporate funds of

Colleges by any kind of direct taxation that the Syndicate felt

obliged to abandon the notion of obtaining the necessary funds from

this source, and accordingly to limit the number of objects which they

should recommend the Senate to accomplish.”

External authority was necessary before the colleges would submit

to taxation for University purposes, and it was left to the Royal

Commission of 1877 to carry into effect many of the suggestions

made by the Syndicate. Meanwhile they contented themselves with

recommending means for raising an annual stipend of £660 for the

professor, demonstrator, and assistant, and a capital sum of £5,000, or

thereabouts, for the expenses of a building.

The Syndicate’s Report was issued in an amended form in the May term of

1870, and before any decision was taken on it the Vice-Chancellor, Dr.

Atkinson, on October 13th, 1870, published “the following munificent

offer of his grace the Duke of Devonshire, the Chancellor of the

University,” who had been chairman of the Commission on Scientific

Education.

“Holker Hall, Grange, Lancashire.

“MY DEAR MR. VICE-CHANCELLOR,--I have the honour to address you

for the purpose of making an offer to the University, which, if

you see no objection, I shall be much obliged to you to submit

in such manner as you may think fit for the consideration of

the Council and the University.

“I find in the report dated February 29th, 1869, of the

Physical Science Syndicate, recommending the establishment of

a Professor and Demonstrator of Experimental Physics, that the

buildings and apparatus required for this department of science

are estimated to cost £6,300.

“I am desirous to assist the University in carrying this

recommendation into effect, and shall accordingly be prepared

to provide the funds required for the building and apparatus as

soon as the University shall have in other respects completed

its arrangements for teaching Experimental Physics, and shall

have approved the plan of the building.

“I remain, my dear Mr. Vice-Chancellor,

“Yours very faithfully,

“DEVONSHIRE.”

By his generous action the University was relieved from all expense

connected with the building. A Grace establishing a Professorship of

Experimental Physics was confirmed by the Senate February 9th, 1871,

and March 8th was fixed for the election.

Meanwhile who was to be Professor? Sir W. Thomson’s name had been

mentioned, but he, it was known, would not accept the post. Maxwell

was then applied to, and at first he was unwilling to leave Glenlair.

Professor Stokes, the Hon. J. W. Strutt (Lord Rayleigh), Mr. Blore

of Trinity, and others wrote to him. Lord Rayleigh’s letter[35] is as

follows:

“Cambridge, 14th February, 1871.

“When I came here last Friday I found everyone talking about

the new professorship, and hoping that you would come. Thomson,

it seems, has definitely declined.... There is no one here in

the least fit for the post. What is wanted by most who know

anything about it is not so much a lecturer as a mathematician

who has actual experience in experimenting, and who might

direct the energies of the younger Fellows and bachelors into

a proper channel. There must be many who would be willing to

work under a competent man, and who, while learning themselves,

would materially assist him.... I hope you may be induced to

come; if not, I don’t know who it is to be. Do not trouble to

answer me about this, as I believe others have written to you

about it.”

On the 15th of February, Maxwell wrote to Mr. Blore:--

“I had no intention of applying for the post when I got your

letter, and I have none now, unless I come to see that I can do

some good by it.” The letter continues:--“The class of Physical

Investigations, which might be undertaken with the help of men

of Cambridge education, and which would be creditable to the

University, demand in general a considerable amount of dull

labour, which may or may not be attractive to the pupils.”

However, on the 24th of February, Mr. Blore wrote to the Electoral

Roll:--

“I am authorised to give notice that Mr. John (_sic_) Clerk Maxwell,

F.R.S., formerly Professor of Natural Philosophy at Aberdeen, and

at King’s College, London, is a candidate for the professorship of

Experimental Physics.”

Maxwell was elected without opposition. Writing[36] to his wife from

Cambridge, 20th March, 1871, he says:--

“There are two parties about the professorship. One wants

popular lectures, and the other cares more for experimental

work. I think there should be a gradation--popular lectures and

rough experiments for the masses; real experiments for real

students; and laborious experiments for first-rate men like

Trotter and Stuart and Strutt.”

While in a letter[37] from Glenlair to C. J. Munro, dated March 15th,

1871, he writes:--“The Experimental Physics at Cambridge is not built

yet, but we are going to try. The desideratum is to set a Don and a

Freshman to observe and register (say) the vibrations of a magnet

together, or the Don to turn a watch and the Freshman to observe and

govern him.”

In October he delivered his Introductory Lecture. A few quotations will

show the spirit in which he approached his task.

“In a course of Experimental Physics we may consider either

the Physics or the Experiments as the leading feature. We may

either employ the experiments to illustrate the phenomena of

a particular branch of Physics, or we may make some physical

research in order to exemplify a particular experimental

method. In the order of time, we should begin, in the Lecture

Room, with a course of lectures on some branch of Physics

aided by experiments of illustration, and conclude, in the

Laboratory, with a course of experiments of research.

“Let me say a few words on these two classes of

experiments--Experiments of Illustration and Experiments of

Research. The aim of an experiment of illustration is to throw

light upon some scientific idea so that the student may be

enabled to grasp it. The circumstances of the experiment are

so arranged that the phenomenon which we wish to observe or to

exhibit is brought into prominence, instead of being obscured

and entangled among other phenomena, as it is when it occurs

in the ordinary course of nature. To exhibit illustrative

experiments, to encourage others to make them, and to cultivate

in every way the ideas on which they throw light, forms an

important part of our duty. The simpler the materials of an

illustrative experiment, and the more familiar they are to the

student, the more thoroughly is he likely to acquire the idea

which it is meant to illustrate. The educational value of such

experiments is often inversely proportional to the complexity

of the apparatus. The student who uses home-made apparatus,

which is always going wrong, often learns more than one who has

the use of carefully adjusted instruments, to which he is apt

to trust, and which he dares not take to pieces.

“It is very necessary that those who are trying to learn from

books the facts of physical science should be enabled by the

help of a few illustrative experiments to recognise these facts

when they meet with them out of doors. Science appears to us

with a very different aspect after we have found out that it is

not in lecture-rooms only, and by means of the electric light

projected on a screen, that we may witness physical phenomena,

but that we may find illustrations of the highest doctrines of

science in games and gymnastics, in travelling by land and by

water, in storms of the air and of the sea, and wherever there

is matter in motion.

“If, therefore, we desire, for our own advantage and for the

honour of our University, that the Devonshire Laboratory should

be successful, we must endeavour to maintain it in living union

with the other organs and faculties of our learned body. We

shall therefore first consider the relation in which we stand

to those mathematical studies which have so long flourished

among us, which deal with our own subjects, and which differ

from our experimental studies only in the mode in which they

are presented to the mind.

“There is no more powerful method for introducing knowledge

into the mind than that of presenting it in as many different

ways as we can. When the ideas, after entering through

different gateways, effect a junction in the citadel of the

mind, the position they occupy becomes impregnable. Opticians

tell us that the mental combination of the views of an object

which we obtain from stations no further apart than our two

eyes is sufficient to produce in our minds an impression of the

solidity of the object seen; and we find that this impression

is produced even when we are aware that we are really looking

at two flat pictures placed in a stereoscope. It is therefore

natural to expect that the knowledge of physical science

obtained by the combined use of mathematical analysis and

experimental research will be of a more solid, available, and

enduring kind than that possessed by the mere mathematician or

the mere experimenter.

“But what will be the effect on the University if men pursuing

that course of reading which has produced so many distinguished

Wranglers turn aside to work experiments? Will not their

attendance at the Laboratory count not merely as time withdrawn

from their more legitimate studies, but as the introduction of

a disturbing element, tainting their mathematical conceptions

with material imagery, and sapping their faith in the formulæ

of the text-books? Besides this, we have already heard

complaints of the undue extension of our studies, and of the

strain put upon our questionists by the weight of learning

which they try to carry with them into the Senate-House. If we

now ask them to get up their subjects not only by books and

writing, but at the same time by observation and manipulation,

will they not break down altogether? The Physical Laboratory,

we are told, may perhaps be useful to those who are going out

in Natural Science, and who do not take in Mathematics, but

to attempt to combine both kinds of study during the time of

residence at the University is more than one mind can bear.

“No doubt there is some reason for this feeling. Many of us

have already overcome the initial difficulties of mathematical

training. When we now go on with our study, we feel that it

requires exertion and involves fatigue, but we are confident

that if we only work hard our progress will be certain.

“Some of us, on the other hand, may have had some experience

of the routine of experimental work. As soon as we can read

scales, observe times, focus telescopes, and so on, this kind

of work ceases to require any great mental effort. We may,

perhaps, tire our eyes and weary our backs, but we do not

greatly fatigue our minds.

“It is not till we attempt to bring the theoretical part of

our training into contact with the practical that we begin to

experience the full effect of what Faraday has called ‘mental

inertia’--not only the difficulty of recognising, among the

concrete objects before us, the abstract relation which we have

learned from books, but the distracting pain of wrenching the

mind away from the symbols to the objects, and from the objects

back to the symbols. This, however, is the price we have to pay

for new ideas.

“But when we have overcome these difficulties, and successfully

bridged over the gulph between the abstract and the concrete,

it is not a mere piece of knowledge that we have obtained; we

have acquired the rudiment of a permanent mental endowment.

When, by a repetition of efforts of this kind, we have more

fully developed the scientific faculty, the exercise of this

faculty in detecting scientific principles in nature, and in

directing practice by theory, is no longer irksome, but becomes

an unfailing source of enjoyment, to which we return so often

that at last even our careless thoughts begin to run in a

scientific channel.

“Our principal work, however, in the Laboratory must be to

acquaint ourselves with all kinds of scientific methods, to

compare them and to estimate their value. It will, I think,

be a result worthy of our University, and more likely to be

accomplished here than in any private laboratory, if, by the

free and full discussion of the relative value of different

scientific procedures, we succeed in forming a school of

scientific criticism and in assisting the development of the

doctrine of method.

“But admitting that a practical acquaintance with the methods

of Physical Science is an essential part of a mathematical

and scientific education, we may be asked whether we are not

attributing too much importance to science altogether as part

of a liberal education.

“Fortunately, there is no question here whether the University

should continue to be a place of liberal education, or

should devote itself to preparing young men for particular

professions. Hence, though some of us may, I hope, see reason

to make the pursuit of science the main business of our lives,

it must be one of our most constant aims to maintain a living

connexion between our work and the other liberal studies of

Cambridge, whether literary, philological, historical, or

philosophical.

“There is a narrow professional spirit which may grow up among

men of science just as it does among men who practise any other

special business. But surely a University is the very place

where we should be able to overcome this tendency of men to

become, as it were, granulated into small worlds, which are

all the more worldly for their very smallness? We lose the

advantage of having men of varied pursuits collected into one

body if we do not endeavour to imbibe some of the spirit even

of those whose special branch of learning is different from our

own.”

Another expression of his views on the position of Physics at the time

will be found in his address to Section A of the British Association,

when President at the Liverpool meeting of 1870.

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