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The study of the chemical composition of, and of actual or possible chemical changes in, the crust of the earth. -- Ge`o*chem"ic*al (#), a. --Ge`o*chem"ist (#), n.

ed (1885), in a silver ore (argyrodite) at Freiberg. It is a brittle, silver-white metal, chemically intermediate between the metals and nonmetals, resembles tin, and is in general identical with the predicted ekasilicon. Symbol Ge. Atomic weight 72.3.

bile united with cholic acid. It is also formed from gelatin by decomposition with acids. Chemically, it is amido-acetic acid. Called also glycin, and glycocin.

ion and evaporation, and which, as manifested in fire, the sun's rays, mechanical action, chemical combination, etc., becomes directly known to us through the sense of feeling. In its nature heat is a mode if motion, being in general a form of molecular disturbance or vibration. It was formerly supposed to be a subtile…

by the action of strong acetic acid and common salt; -- called also Teichmann's crystals. Chemically, it is a hydrochloride of hematin.

Of, pertaining to, or taught by, Hermes Trismegistus; as, hermetic philosophy. Hence: Alchemical; chemic. "Delusions of the hermetic art." Burke. The alchemists, as the people were called who tried to make gold, considered themselves followers of Hermes, and often called themselves Hermetic philosophers. A. B. Buckley.…

In an hermetical manner; chemically. Boyle.

Unrelated in chemical composition, though similar or indentical in certain other respects; as, borax and augite are homoemorphous, but heteromerous.

An alkaloid, prepared from atropine, and from other sources. It is chemically related to atropine, and is used for the same purpose.

A near similarity of crystalline forms between unlike chemical compounds. See Isomorphism.

of the paraffin series. In an extended sense, the term is applied to the relation between chemical elements of the same group; as, chlorine, bromine, and iodine are said to be in homology with each other. Cf. Heterology. General homology (Biol.), the higher relation which a series of parts, or a single part, bears to t…

A chemical substance formed in one organ and carried in the circulation to another organ on which it exerts a stimulating effect; thus, according to Starling, the gastric glands are stimulated by a hormone from the pyloric mucous membrane.

The act of becoming, or state of being, a hydrate. Water of hydration (Chem.), water chemically combined with some substance to form a hydrate; -- distinguished from water of crystallization.

s in water. It is a typical acid, and is an indispensable agent in commercial and general chemical work. Called also muriatic, and chlorhydric, acid.

e action of sulphuric acid on yellow prussiate of potassium (potassium ferrocyanide), and chemically resembles hydrochloric and hydrobromic acids. Called also prussic acid, hydrogen cyanide, etc.

It is very inflammable, and is an ingredient of coal gas and water gas. It is standard of chemical equivalents or combining weights, and also of valence, being the typical monad. Symbol H. Atomic weight 1.

A chemical process involving the addition of the elements of water.

r caustic alkali. Encyc. Brit. Hydrolitic ferment (Physiol. Chem.), a ferment, enzyme, or chemical ferment, which acts only in the presence of water, and which causes the substance acted upon to take up a molecule of water. Thus, diastase of malt, ptyalin of saliva, and boiling dilute sulphuric acid all convert starch…

A physician who explained or treated diseases upon chemical principles; one who practiced iatrochemistry.

physicians in Flanders, in the 17th century, who held that health depends upon the proper chemical relations of the fluids of the body, and who endeavored to explain the conditions of health or disease by chemical principles.