ass Chemical Analysis of the Atmosphere. 279 
it goes to confirm the views which have been here taken of the subs 
ject. If the fingers make a series of movements, in such sure and 
rapid succession, it is not simply because the mind has time to de 
termine and will each movement, but because it has been accustom- 
ed so to move them. It is a matter of habit. This is the decision 
of the great mass of mankind: and there is nothing in the whole 
circle of intellectual phenomena to contravene it. 7 
we have arrived at habit, we have arrived apparently at the 
eldinate fact. Every body knows that the mind is most apt to operate, 
and most readily, in the way in which it has operated be- 
fore. But the question why or how it is so, probably admits of the 
sole answer, that itis an ordinance of the Creator. It is an ordinance 
designed and calculated to give to idleness and vice their punishment, 
and its reward to diligence. 
If these views are correct, the proper and philosophical definition 
of memory is not, the recalling of ideas or images laid up in the 
mind, or the power of doing it ; nor is it even, the renewing of former 
impressions and reflections, or the power of doing it, except in those 
doubtful cases in which the mind itself may produce actual sensations 5 
but it is, the acts of the mind in ways to which it has been 
or the force of habit urging, disposing or helping the mind in the 
performance of customary acts. Memory is either the influence or 
power of mental habit, or the results of that habit; and as a neces 
sary consequence, the improvement of the memory mainly pi 
the frequency and —— of mental action. 
res Noy. 
Arr. 1X.—Memoir on the Chemical Analysis of the Ainospr 
by M. Brunner, Prof. of Chemistry at Berne. Translated. for 
this Journal by Prof. Griscom. 
Aa examination of the chemical constitution of the atconsphesst 
‘a matter of such great importance, that we are not surprised 10 find 
‘so many efforts have been made to bring it to the highest aerate de- 
gree of perfection. The attention of philosophers has been chiefly 
-directed to the four substances of which the atmosphere, in its ordinary 
state, is always constituted,—to the determination of the proportions 
of these substances with as much exactness as the state.of —— 
and the accuracy of our instruments will permit. 
The azote and oxygen form the great mass of atmospheric Sid, 
and in proportions which appear almost entirely constant,—at least 
