27 
suffering of ordinary physical disease. We are ill we know not of what; and yet 
the sensibility of the system is so unimpaired by our indescribable illness, that 
acute bodily pain would be deliverance from such suffering. 
A future opportunity may occur for inquiring into the peculiar tone of the 
sentient system in man which is most accordant with efficient mental operation; 
but we may, in the mean time, remark that this is a medium state, and that the 
bodily sensibility may be either too dull or too acute for the exercise of vigorous 
thought, or the performance of useful action. If it is too obtuse, the mind does not 
receive the impression, and, of course, neither thought nor action can follow; and 
if, on the other hand, it is too acute, the anguish of the bodily feeling makes so 
strong an impression, that the mind is incapable of applying its common mode of 
judgment, by analogy, to the cause of the impression, and its effect external of 
the body. It is the mental operation which is injured both by too much obtuse¬ 
ness and too much acuteness of the sense: and in each case the conduct of the 
human being approximates that of a mindless animal; and in the extreme cases 
the approximation may be so close that no observation can draw the line of dis¬ 
tinction between them. 
It is these extreme cases of insensibility and sensibility of the body, to which 
the names of idiocy and mania are given. In common language, we call both of 
them mental derangements ; but no word can be worse applied. The mind, in 
order to be immortal, must be perfectly simple, and incapable of any division of 
parts, even in imagination ; because, if the existence of separate parts were ima¬ 
ginable, the separation of those parts would also be imaginable ; and this separa¬ 
tion would be the death of the mind, and man would be brought down to the level 
of the beasts that perish. But, if composition be inconsistent with our original 
idea of mind, mental derangement must be equally so; for it is not possible to 
derange one single existence, be that existence what it may. To return from this 
digression, which, however, is far from being an useless one: we can see how 
wise and how good it is that the sentient part of the human frame is so tempered 
that it does not habitually break in upon the operations of mind; and, because 
we are worse barometers than the animals which we have mentioned, and, indeed, 
than all mindless animals, we are thinkers and philosophers, and they are not. 
The animal which has the action instantly consequent upon the sensation, 
without any intermediate mental judgment by comparison with former experience, 
is, of course, wholly at the mercy of external circumstances, and compelled as 
necessarily and as instantly to obey every change of these to the full amount of 
its influence, as a fragment which the lightning shivers from the precipice is ne¬ 
cessitated to descend by the force of gravitation. It is this perfect obedience of 
the system of mindless animals to the circumstances of Nature external of them, 
which renders the study of them so very valuable for meteorological purposes ; 
and this study deserves far more attention than it has hitherto received. 
e 2 
R. M. 
