Page:The American Cyclopædia (1879) Volume XIII.djvu/291

 PEPPEKIDGE a week in order to keep up a supply; any gar- den soil will suit it, and the seeds, when sown in shallow drills, come up very quickly ; with us it can only be had in good condition early in the season, as hot weather causes it to run to flower very soon ; in England the leaves are plucked separately, leaving the plant to pro- duce others, but in our gardens it is generally cut. There are plain and curled varieties, and one with yellowish leaves called golden and Australian pepper grass. A related species found abundantly upon the shores of New Zealand was much valued by the early mari- ners as a remedy for scurvy. PEPPERIDGE. See BLACK GUM. PEPPERMINT. See MINT. PEPPER TREE, the popular name on the Pa- cific coast for schinus molle, a South American tree much cultivated in California and else- where. The genus schinus (the Greek name for the mastic tree, and applied to this related genus) comprises about a dozen tropical Ameri- can trees and shrubs, and belongs to the ana- cardiacece, the cashew-nut family, of which the sumachs are our most familiar examples. The pepper tree or false pepper grows 20 ft. or more high, with alternate unequally pinnate leaves, which have about 10 pairs of serrate leaflets and a longer terminal one ; the flowers are dioecious, in axillary or terminal panicles ; stamens 10 ; ovary one ; the fruit is a berry of the size of a small pea, having a highly pol- ished skin of a bright rose color, enclosing a succulent portion within which is a stony one- seeded nut, the surface of which is marked by six furrows containing oil. All parts of the PEPSIN 2S1 Pepper Tree (Schinus molle). tree are aromatic, being pervaded by a resinous liquid ; their odor, especially that of the fruit, as well as taste, is almost precisely like that of black pepper. If the leaves of the tree are broken and the fragments thrown upon water, singularly life-like movements take place ; the fragments appear to have the power of motion, and travel about the surface of the water by a series of jerks in a most interesting and amu- sing manner. This phenomenon is due to the sudden expulsion of the resinous oil from the tissues of the leaf, which reacting against the water propels the fragment of leaf ; the forcing out of the oil is apparently due to the action of water upon the cells containing it, as it is noticed that the air in the vicinity of the trees is always filled with their peculiar fragrance immediately after a shower. In Peru the tree is called molle ormulli; in that country the root is used medicinally, and a sort of resin which exudes from the stems is chewed to im- prove the gums ; it is also purgative ; the ber- ries are used to make a sort of wine. In Cali- fornia the tree makes a handsome head, and its fragrance and the beauty of its fruit com- mend it for planting. PEPSIN, the substance contained in the gas- tric juice and in the mucous membrane of the stomach, to which, in addition to its acidity, the gastric juice owes its power of converting the albuminoid constituents of the food into soluble peptones. It has probably never been isolated in a state of purity. Pepsin mingled with more or less foreign material may be ob- tained from the stomach of animals and used for the promotion of digestion in other animals or in the reagent glass. The various preparations containing it in a state of greater or less puri- ty are called pepsines. These vary, as regards their digestive strength, within very wide lim- its. Several processes have been employed, usually beginning with the maceration in acid- ulated water or in wine of prepared and gen- tly washed mucous membranes from calves' or pigs' stomachs. The latter menstruum gives rennet or pepsin wine. The acid solution may be preserved with glycerine or treated with various reagents to obtain solid pepsin. The process of Mr. Scheffer of Louisville, which gives a product both elegant and effective, pre- cipitates the pepsin with a concentrated solu- tion of common salt. It is then dried, and di- luted with sugar of milk to a fixed strength. Other forms of pepsin are mixed with starch. The mucus may be scraped from the stomach and dried on a glass plate. The filtered gas- tric juice itself has also been used. If coagu- lated white of eggs or pieces of fibrine be placed in an acidulated solution of pepsin and kept at the temperature of the body, they will be gradually softened and dissolved. This process is a good one for estimating the rela- tive value of different kinds of pepsin, the best of course dissolving the most. It does not, however, represent the extreme limits of its efficacy in the stomach, since it has been found by Mr. Scheffer that by separating a portion of the digested product, this in its turn is capable of continuing the process in an acid solution, the quantity of albumen which could have been digested by the original pepsin with- out renewal of acid being thus vastly exceeded.