Having expressed a decided opinion that there are, in all living bodies, chemical as well as mechanical phenomena, which, in the present state of our knowledge, ought to be designated as Vital, and referred to the operation of laws, distinct from those that regulate the chemical changes of inanimate matter, and observing that this opinion is controverted, and that the view of the chemical phenomena of life which I have maintained, is rejected as unphilosophical and delusive by two authors of high scientific reputation—Baron Humboldt and Dr Daubeny,—and that the judgment of other authors of acknowledged character on this subject is not clearly expressed, and seems to me to involve it in unnecessary obscurity, I am led to hope that some farther explanations may be of some use in establishing the first principles of a Science which, as it appears to me, has suffered, in several instances, not so much from want of facts, as from hypothetical and erroneous inferences, drawn from facts that are already known.