NATURE 

THURSDAY, JULY 6, 1871 


SENSATION AND SCIENCE 
HE morbid craving for excitement, which is charac- 
teristic of mental indolence, as well as of effete 
civilisation, has led to the introduction of Sensation (as 
it is commonly called), not merely into our newspapers 
and novels, but even into our pulpits. It could not be 
expected that our popular scientific lectures would long 
escape the contamination. We have watched with regret 
its gradual introduction and development, and have often 
meditated an article on the subject. But now, when a splen- 
did opportunity has come, we feel how unfit we are for the 
task. None but a Spurgeon can effectively criticise a 
Spurgeon;none buta Saturday Reviewer could be expected 
to tackle with delicacy and yet with vigour the gifted 
author of the “ Girl of the Period.” So we must content 
ourselves with the spectacle of the Rev. Prof. Haughton 
as criticised by himself. We have not been able to attend 
his recent lectures at the Royal Institution, but we have 
it on excellent authority that they were racy (z.e. sensa- 
tional) in the extreme. Happily we find in the British 
Medical Fournal what is described as an authorised ver- 
sion of them. A few extracts from this will enable us to 
dispense with a great deal of comment. We shall first 
take the Science, and then permit the Sensation to speak 
for itself. . 
Prof. Haughton’s subject is The Principle of Least 
Action in Nature; and we are told that he believes he has 
succeeded in discovering in this the true principle on 
which the Science of Animal Mechanics must be founded, 
and has been enabled to sketch out the broad outlines of 
its foundation. 
Maupertuis’s Principle of Least Action is indeed “ well 
known to mathematicians,” but is by no means easy of 
explanation to the ordinary reader. We can, therefore, 
sympathise with the lecturer in his repeated failures to 
make it intelligible. But we cannot admit any justifi- 
cation of the constant use of the same words, sometimes 
in one sense, sometimes in a totally different one. Toa 
mathematician (Prof. Haughton speaks as at once mathe- 
matician, anatomist, medical man, natural philosopher, 
“expert” at shot-drill, the crank, and the treadmill, 
clergyman, &c., &c., and even as potential farmer and 
landlord-shooter !) we should have thought that, when 
once x, y, z, or whatever else, is introduced, it has and 
continues to have a definite meaning, until zz a new 
problem it comes to be applied to something possibly 
quite different. How then can we account for such 
sentences as the following ?— 
“The great problem—the problem of doing a given 
amount of work wth a minimum of effort.” 
“Nature aims at producing a given quantity of work 
with the least quantity of material.” 
“T could show that these [tendons of the legs andarms 
of animals] are constructed w7th a wonderful economy of 
force of the same kind as that with which the bee con- 
structs its cell” 
“ By what force, or by what intelligence, do the limbs of 
animals describe their proper path? Who places the 
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177 

socket of each joint in the exact position (which can be 
calculated with unerring certainty by mathematics) which 
enables the muscle to perform its allotted task with the 
least amount of trouble to itself 2” 
“The Principle of Least Action is that the arrangement 
and mutual position of all muscular fibres, bones, and 
joints must be such as to produce the required effect wth 
the minimum amount of muscular tissue.” 
“ Before proceeding to apply this principle of least action 
or least trouble to nature,” &c. 
In all these extracts the italics are ours. If the reader 
but glance them over, he will not require to read the lec- 
tures to see what a very Proteus is this so-called principle. 
There is no knowing where to have it. It is a minimum, 
an economy, a least quantity, and what not ; sometimes 
of effort, sometimes of material, then of trouble, andanon 
of muscular tissue, or of force of the same kind as that 
with which the bee constructs its cell! But the most 
curious feature about it is that in none of its metamor- 
phoses does it in the slightest degree resemble the least 
action of Maupertuis, with which it would seem through- 
out to be held as identical. 
Even in his remarks on this perfectly definite mathe- 
matical question, Prof, Haughton commits a grave error, 
for he says :— 
“Tf I take the points A and B in the planet’s path, S 
representing the sun, I only require to know those points 
A and B, and the sun S, to calculate for you, from the 
Principle of Least Action—which I can do to the millionth 
part of an inch at each point of this orbit—the path that 
the planet must describe, on the supposition that it is a 
lazy, intelligent animal, trying to swim round the sun in 
such a manner as to give the least trouble to itself.” 
It seems to us that all that the principle of least 
action can tell us, is that, supposing the sun’s attraction 
to vary inversely as the square of the distance, the 
planet will describe some conic section or other, whose 
focus is S, and which passes through A and B. Which 
it will be of the innumerable conics satisfying these con- 
ditions, ellipse, parabola, or hyperbola (or possibly circle) 
there is nothing to indicate, within quadrillions of miles 
—yet we are told it can be done to the millionth of an 
inch!! As to what a “lazy, intelligent animal” (of 
course, not acted on by gravity) would do in “trying to 
swim [in what ?] round the sun,” we unfortunately possess 
no information. But this is merely another proof that we 
are dealing with Sensation where we looked for Science. 
Here we have caught our instructor in a palpable and 
inexcusable blunder, and we could easily point out many 
others of a similar kind in his remarks on light, &c. It 
is not so easy to do so, or rather to make the general reader 
aware that we have done so, when he leaves strictly 
mathematical applications, and plunges headlong into a 
wild sea of speculation without previous careful defini- 
tion of his terms. These terms are, in fact, as he em- 
ploys them, so elastic, that it is only by contrasting (as 
we did above) portions of his lectures with other portions 
in which the same words acquire other and different 
meanings, or in which different words are employed for 
the same meaning, that we see how excessively loose and 
slipshod is the whole affair. Another little group of 
quotations will admirably illustrate this :— 
“The law of /east action is attended to in every 
L 
