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the animal fire, and then the impressed molecules, losing condi- 
tion for activity, and coming to rest, cease, functionally to exist. 
But they do not cease actually to exist ; because, whether 
they be bound in ice or bound by pressure, we see that when they 
are unloosed they can return, if the body can supply them with 
caloric, to ’full vigour. Indeed, the images of the brain, once 
well developed and fixed, can only be obscured by derangement 
of brain matter, and can only be destroyed by disintegration of 
brain matter. Cases have occurred in which, under pressure of 
brain, a man has been for months dead to the outer world, and, 
on recovery has remembered what preceded his accident, show- 
ing thus that the imagery of his brain remained intact ; and, as 
I have said already, an animal with a frozen brain, when it is 
restored, will not show an evidence of a lost faculty. By dis- 
integration of brain matter the world within of the world with- 
out only dissolves. This disintegration is, in all men and ani- 
mals, going on slowly, and thus memory becomes defective. In 
second childishness this gradual metamorphosis, this natural mode 
of removing the world and its past from the man, is completed ; 
it is the dissolving view of nature. In the vigorous the imagery 
of the brain is finally destroyed by death alone, and by death 
not of necessity immediately, but with the after disintegration 
of structure. A brain frozen in a living animal, and with the 
animal crystallised in ice, would retain, in that condition, the 
imagery with which it was replete for any grasp of time ; for 
time is no element when there is no change, nor is it recog- 
nisable by aught except change of matter by force. When I 
wind up my watch I put into it so much force, which force is 
expended in moving so much matter, and the measure of that 
movement is the measure of motion, — time. 
The force called caloric, then — the force we liberate in the 
combustion of blood — is the sustaining force of the brain, but 
it is not the only form of force to which the brain is im- 
pressionable when its natural condition is maintained. Through 
the eye calorific force does not pass to the brain but is cut off, 
yet the form of force called light, and probably the actinic force, 
make way ; while through the ear and tactile skin common 
mechanical force finds ingress. We see, we hear, we feel, in 
fine, by the direct action of forces other than caloric, but 
without caloric as the base these are unavailing, for an animal 
with a frozen brain cannot be awakened neither by light, nor by 
noise, nor by touch ; if it could a dead animal could be awakened 
by the same means. 
Sleep and Dreams. 
The course of our research leads us, as we have seen, to con- 
template the condition of the brain in its active state, and under 
