PURVEY'ORS, ARMY, were officers charged with superintending the civil affairs of army hospitals, as the payment of ineu, procuring provisions, medical comfort's, bedding, etc. The purveyor acted independently of the medical officer, and was responsible through the purveyor-in-chief to the secretary of war. The department con sisted of a purveyor-in-chief, principal purveyors, purveyors, deputy-purveyors, and clerks. The purveyor-in-chief rai*ed with a colonel in the army, and bad a salary of £547 per annum, rising to h730 after long service. In 1868 the department was merged with others in the control department; and on the abolition of the latter in 1875 its functions passed to the commissariat and transport department: PUS is a well-known product of inflammation, and occurs as a thick yellow creamy fluid, differing from all other morbid exudations in containing a large number of cor puscles, having a soft and fatty feeling when rubbed between the fingers, a peculiar odor, usually au alkaline reaction, and a specific gravity of about 1.032. the blood, it consists of certain definite microscopic elements, and of an intercellular fluid or serum in which they swim.
The microscopic elements are: 1. The pus-corpuscles, which, both in their microsco pical and chemical relations, seem to be identical with the lymph-corpuscles, or colorless blood-cells; in diameter, they range from 0.004 to 0.005 of a line, and each corpuscle
consists of a cell-wall, which often appears granular, of viscid transparent contents, and of a nucleus which is adherent to the cell-wall, and which can be rendered much more apparent by the. addition of acetic add, 2. Molecular granules, and 3. Pat-globules. The serum of pus is perfeetly,clear, of a slightly yellow color, and coagulates on heating into a thick white mass..
The chemical constituents of pus arc water (varying from 769 to 907 in 1000 parts), albumen (from 44 to 180); fats (from 9 to 25); extractive matter (from 19 to 29); and inorganic salts (from 6 to 13); in addition to which, mucin, pyin, glycin, urea. etc., are occasionally present. Of the inorganic or mineral constituents, the soluble salts tire to the insoluble in the ratio of 8 to 1, and the chloride of sodium (the chief of the soluble salts) is three times as abundant as in the serum of the blood. The mode of formation. of pus is described in the article SUPPURATION.