"Believing that no man will labour in the strenuous and unremitting manner that Mr. Hunter did, and to the detriment of his own private interest, without some strong incentive; I have supposed that at an early period he conceived those notions of life which were confirmed by his future inquiries and experiments. He began his observations on the incubated egg, in the year 1755, which must either have suggested or corroborated all his opinions with regard to the cause of the vital phenomena. He perceived that, however different in form and faculty, every creature was nevertheless allied to himself, because it was a living being; and therefore he became solicitous to inquire how the vital processes were carried on in all the varieties of animal and even vegetable existence." OF GENIUS AND JUDGMENT. "In the progress of science, genius with light and airy steps often far precedes judgment, which proceeds slowly, and either finds or forms a road along which all may proceed with facility and security; but the _direction_ of the course of judgment is often suggested, and its actions are excited and accelerated, by the invocations of preceding genius[51]." REITERATION OF THE DENIAL THAT HE IDENTIFIED LIFE WITH ELECTRICITY. "As Sir H. Davy's experiments fully prove that electricity may be superadded to, and that it enters into, the composition of all those substances we call matter, I felt satisfied with the establishment of the philosophy of Mr. Hunter's views, nor thought it necessary to proceed further, but merely added: 'It is not meant to be affirmed that electricity is life.' I only mean to argue in favour of Mr. Hunter's theory, by showing that a subtile substance of a quickly and powerfully mobile nature seems to pervade everything, and appears to be the life of the world; and that therefore it is probable a similar substance pervades organized bodies, and is the life of these bodies. I am concerned, yet obliged, to detain you by this recapitulation, because my meaning has been either misunderstood or misrepresented[52]." CHEMISTRY OF LIFE. "He (Mr. Hunter) told us that life was a great chemist, and, even in a seemingly quiescent state, had the power of resisting the operations of external chemical agency, and thereby preventing the decomposition of those bodies in which it resided. Thus seeds may lie buried far beneath the surface of the earth for a great length of time without decaying, but being thrown up, they vegetate. Mr. Hunter showed us that this chemist, 'Life,' had the power of regulating the temperature of the substances in which it resides[53]." INTERESTING; ALSO SIGNIFICANT IN REGARD TO WHAT ARE PROBABLY THE REAL SOURCES OF ANIMAL HEAT, AND IN RELATION TO THE LUNGS, WHICH WE HAVE CONTENDED ARE REFRIGERATING AND NOT HEATING ORGANS.