Feb. 16, 1871] 
NATURE 
315 

the masses of clouds came over Adams and Jefferson, I 
looked until I almost persuaded myself that there were 
immense icebergs coming from the uplifted frozen North, 
but the illusion vanished as the summits appeared above 
the clouds. But what was remarkable is that the next 
day was pleasant. 
“ During the last two weeks in November, the average 
of the thermometer was 16°. The wind was north-west 
nearly the whole time. The weather was generally very 
mild, and the number of clear days was much greater than 
the average.” 
We may add to this interesting account that the daily 
telegrams received from the mountain have been full of | 
interest. A temperature of 40° below zero has not been 
uncommon, and we may well hope that the efforts of the 
solitary watchers on the inclement mountain-top will 
tend to advance the science of which they are such 
devoted students. 


SCIENCE IN VICTOKIA 
HOSE who have read the Marquis de Beauvoir’s 
“Voyage round the World” will recollect the high 
praise with which he speaks of Sir Redmond Barry’s 
prolonged and continuous efforts for the advancement of 
Science in Victoria. His latest good deed in this direction 
is the aid which he has afforded in the establishment of 
a School of Mines at Ballarat, which, to use his own 
words, may now be regarded as “‘an accomplished fact,” 
since “ everything connected with its establishment and 
maintenance has been thoroughly debated and deter- 
mined on.” The prospectus of the Institution states that 
“the object sought to be obtained is the combination of 
the highest scientific with the most practical training for 
all men engaged in the enterprise of mining in its various 
branches — whether so engaged as mining managers, 
engineers, surveyors, mechanists, working miners, di- 
rectors or promoters of companies ;” and, as there is 
every reason to believe that the school will be supported 
by the Government, by the several mining boards, and 
by the general «public, we may hope to see it in actual 
operation ina few months. 
We have not space to give a sketch of Sir Redmond 
Barry’s excellent address, further than to remark that he 
points out the general bearings of chemistry, electricity, 
geology, steam, &c., on the progress of mining ; and we 
must content ourselves with the following extract relating 
to the progress of Science in Australia :— 
“We are not,” he observes, “ even in our time, satisfied 
to import the discoveries of others, and to invite the man 
of science and the skilled artisan to direct their opera- 
tions. Australia can point with a modest satisfaction to 
the invention of Osborne in photo-lithography, and the 
test for blood by Dr. Day ;* to the cure for snake- bites by 
Professor Halford ; to the method of removing pyrites, 
that inveterate enemy of the metallurgist, as well as the 
native alloys, from gold, and toughening the metal by the 
use of chlorine gas, by Mr. Miller of the Sydney Mint ; 
to the scientific preservation of the meat of our redun- 
dant flocks and herds, so largely exported ; and also to 
many others, mention of which would delay us too long.” 

THE CONTRACTION OF THE EARTHt 
"THE phenomena, which were ably presented by the distin- 
guished geologist, Mr. Lesley, to the National Academy 
of Sciences, and which seem to demonstrate that the outer shell 
* A full account of Dr. Day’s remarkable colour-tests for blood and pus 
may be found in Dr. Richardson’s Report on Toxicology in the last number 
of the Medico-Chirurgical Review.—Ep, 
+ From the Proceedings of the American Academy of Arts and Sciences, 
yol, viii. 

of the earth has sensibly shrunk, in some directions at least, 
since its original formation, naturally invite the attention of phy- 
sicists to the possible causes of such a result. The most obvious 
cause of the shrinking of the earth isits cooling. But to shrink two 
per cent. linearly, which is the amount deduced by Mr. Lesley from 
the observed geological phenomena, involves a probable cooling 
of the whole earth of not less than two thousand degrees centi- 
grade, which would require that its original temperature should 
be higher than would be consistent with the solidity of these 
shrunk strata. 
Another source of change of form, which would produce 
shrinkages in different directions in different parts of the earth, 
is to be found in the diminution of oblateness arising from the 
diminished velocity of rotation upon the axis. Such diminution 
of the velocity of rotation has several years ago been shown by 
Mr. Ferrel to be caused by the action of the moon in producing 
the tides ; this is, therefore, a true cause, and it is only necessary 
to examine how great its amount can be under any circumstances. 
This is all which is proposed in the present investigation, and the 
application to facts is reserved for geologists. 
It is sufficient, for the present object, to regard the earth as 
homogeneous. Under this condition Laplace has shown that the 
time of the earth’s rotation could not be less than about one-tenth 
of a day, which corresponds to a ratio of the axis of the equator 
to that of the pole, equal to 2"7197, and an equatorial circum- 
ference 94 per cent. greater than the present one. Such is then 
the amount of shrinking which might have taken place, if any 
cause could be assigned capable of producing so great a reduction 
of the earth’s velocity. The whole surface of the earth would 
have been about 130 per cent. larger than at present. 
But the only cause at present known which would produce a 
sensible reduction of the earth’s velocity is the lunar action upon 
the tides. But in this mutual action between the moon and the 
earth, the common rotation area of the earth and moon must 
remain unchanged. The question then arises, How great a 
reduction of the rotation area of the earth would have passed into 
that of the moon? In this inquiry it may be assumed that the 
moon revolves in a circular orbit in the plane of the earth’s 
equator. 
Now the moon’s rotation area is 3'716 times the earth’s, 
But if, in the origin, it had revolved just in contact with this 
earth, its rotation area would not have been less than 0-480 times 
the earth’s, so that it could not have absorbed a rotation area 
from the earth greater than 3°236 times the earth’s present rotation 
area, and therefore the earth’s rotation area could never have 
exceeded 4'236 times that which it has.at present. But, with 
the maximum velocity of rotation given by Laplace, the earth’s 
rotation area would have been 373 times greater than at present. 
It can never, therefore, have been reduced to so great an extent 
by the moon’s action on the tides. But since, when the oblate- 
ness is small, the rotation area is nearly proportional to the velo- 
city; and the excess of the square of the equatorial above that of 
the polar axis is nearly proportional to the square of the velocity, 
this excess may have been originally nearly eighteen times as 
great as at present, or about 15% per cent. of the square of the 
polar axis. This would correspond to a figure of the earth in 
which the equatorial radius would have been about 2} per cent. 
greater than at present ; so that it is sufficient to account for the 
observed phenomenon. 
This peculiar form of shrinkage would produce the highest 
mountains at the equator, and the tendency of the mountain 
ranges would then be to assume the direction of the meridian. 
But nearer the poles the mountains would be less elevated, and 
would rather tend towards the direction of the parallels of 
latitude. 
It is, next, expedient to consider the mechanical question of 
the loss of living force in the case of the moon’s action upon the 
waters of the earth, and its effect upon their different motions. 
In this connection there are problems worthy of the attention of 
geometers ; such as the relative motions of bodies rotating above 
the same vertical axis, towards which they are drawn by weights, 
and acting upon each other through the friction ontheaxis. For 
one of the bodies a rotating wheel may be substituted. There 
is also the case of two planets revolving about a primary, and 
acting upon each other through some form of friction. 
In this way it will be seen that the planet or satellite once 
formed is constantly removed from the primary, and that planets 
tend to approach each other. It is interesting to consider whether 
this may not be one of the actual problems of nature. 
B. PEIRCE 
