Chemical commerce and its commodities : a valedictory address / by Prof. R. Welch, A.M., at commencement of Hahnemann Medical College, 1866.

  • Welch, R.
Date:
[1866]
Catalogue details

Licence: Public Domain Mark

Credit: Chemical commerce and its commodities : a valedictory address / by Prof. R. Welch, A.M., at commencement of Hahnemann Medical College, 1866. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    they are cold, inert, motionless. They differ as much from the particles of the living world around us as the lifeless mutilated 3e in the dissecting room differs from the vigorous, animated man who sways a multitude or directs an army. In nature, however, these atoms are endowed with life, affections, and the power of motion. They move along the paths marked out for them with as much certainty as that with which the planets revolve in their courses. Next to the sublimity of the doctrine which Christianity teaches in regard to the immortality of the soul, stands the grandeur of the principle which modem chemistry has demon- strated in relation to the eternity of matter. At no two periods since time Began, has the aspect of the earth been the same, and still the identity of its composition as a mass has ever been pre- served. How many and what varied forms of matter has the Great Artisan fashioned from the same materials ! From how few simples have so many compounds—animate and inanimate, bane and antidote—been produced. With what masterly work- manship has the commonest clay been moulded into forms of resplendent beauty; and then as often as the pitcher lias been broken at the fountain, how have the shapelss frag- ments been remoulded into other and still more beautiful forms! Although the circulation of matter is regulated by fixed and immutable laws, still the time that is required to complete a rev- olution is as variable as is the nature of organic structures. The worm feeds upon the leaf of the growing tree, and at the same time gives back the materials to construct the very fiber he is devouring. A fish and plant will live for months in an aqua- rium, almost entirely, on the gases that are passing from one to the other through the medium of the water. Remove tin; plant, and the lively, restless fish dies in a day—dies from the effects of the very substance that gave life to the plant. Remove the fish, and the plant lives for a brief interval upon portions of its decaying members, and then life ceases with the plant as with the fish. An orange-grower sits beneath the branches of the tree he has planted, eating the luscious, ever-ripening fruit, and in an hour the tree may receive back again the materials for forming other fruits to be in their turn devoured.