in exact proportion to the degree of admixture which had been effected of the food with the gastric juice,--an admixture now ascertained to be produced chiefly by the contractile power of the stomach itself. * * * * * The muscular contractions of the stomach being thus under the guidance of the pneumogastric nerve, what are called its _vital_ functions--those by which its life is sustained--viz. circulation, nutrition, secretion, and absorption, are generally considered to be carried on under the influence of the great _sympathetic_ or _ganglionic_ nerve, so called from its very extensive ramifications being supposed to bring the different parts of the system into relation with each other, and which, accordingly, is found to exist in animals that have neither brain nor spinal marrow, nor nerves of voluntary motion. In man, however, the sympathetic nerve receives filaments from the _sentient_ or _feeling_ part of the spinal marrow, probably for the purpose of connecting more intimately the organic with the higher functions of animal life. But as much obscurity still prevails on this subject, and moreover we have no direct control over the action of the ganglionic nerves, I shall not detain the reader with any conjectural discussion, but rather request his attention for a moment to the circumstance that it is through the medium of the nervous communications above hinted at, that the very remarkable influence which all must have experienced and observed as constantly exerted by the mind and stomach on each other, is kept up--an influence so powerful in its effects on both bodily and mental health, as to require special notice when we shall treat of the practical application of the present exposition.