Page:The American Cyclopædia (1879) Volume XIII.djvu/227

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PEASE PEAT 217 PEASE, Calvin, an American clergyman, born at Canaan, Conn., Aug. 12, 1813, died in Bur- lington, Vt., Sept. 17, 1863. He graduated at the university of Vermont in 1838, and in 1842 became professor of Latin and Greek there, and in December, 1855, president of the uni- versity. In the latter year he was ordained to the Congregational ministry, having been licensed to preach about five years previously. He was chosen president of the Vermont board of education on its organization in 1856, and took a leading part in unifying the common school system of the state. In the same year he became president of the Vermont teachers' association. In the winter of 1861-'2, on ac- count of his health, he accepted the pastorate of the first Presbyterian church (Old School) in Rochester, N. Y., where he was especially active during the revival of 1863. He pub- lished several sermons and addresses. PEAT, the partially decomposed remains of vegetation that accumulate in localities which are at all times wet or damp. The mass con- sists of matted roots, leaves, and stems of plants, the forms of which are sometimes distinctly preserved, and at others are lost in the mucky substance produced by their decomposition. It forms layers several feet thick, and in some places repetitions of these are found alterna- ting with others of sand. (See BOG.) There are immense bodies of peat in Ireland, and it also abounds in Scotland and on the continent along the coasts of the North sea. Tracts of peat land occur on the N. E. coast of North America in Labrador, Newfoundland, and An- ticosti, where the summers are not excessively warm, and where frequent fogs give the peat mosses the amount of moisture they require. On the S. coast of Anticosti a plain covered with peat extends more than 80 m., with an average breadth of 2 m. and a thickness of from 3 to 10 ft. In the United States peat is little known south of the state of New York ; but it is met with in bogs of considerable ex- tent in the N. part of that state, in New Eng- gland, and west and north to Iowa, Minnesota, and Canada. Its range is chiefly limited to the temperate zones, and to localities where the climate is moist and the subsoil is imper- vious to water. Darwin says that in the south- ern hemisphere 45 marks its nearest approach to the equator. Very great differences are observable in peat beds. Some peats are gray, and others red or black; the majority when dry are dark brown-red or snuff color. They also vary remarkably in weight and consistence. Some are compact, destitute of fibres or other traces of vegetation, and on drying shrink greatly and yield tough dense masses, which burn readily and make an excellent fuel ; oth- ers are light and porous, and remain so on dry- ing, containing much vegetable matter which is but little advanced in the peaty decompo- sition. Some peats are almost entirely free from mineral matter, and leave when burned but a small percentage of ash ; others contain considerable lime or iron in chemical combi- nation, or sand or clay in mechanical admix- ture. The nature of the vegetation from which peat has been formed has much effect upon its character. Peats chiefly derived from mosses which have grown in the full sunlight have a yellowish red color in their upper layers, which usually becomes darker as we go down, running through brown, until at a considerable depth it is black. Those produced principally from grasses are grayish at the surface, being full of silvery fibres, the skeletons of the grasses and sedges, while below they are commonly black. Moss peat is oftenest fibrous, and when dried forms elastic masses. Grass peat when taken a little below the surface is commonly destitute of fibres, is earthy in appearance when wet, and dries to dense, hard lumps. In Germany the "ripest," most perfectly formed peat is called pitch peat or fat peat ; it is dark brown or black, and comparatively heavy and dense. When moist, it is firm, sticky, and co- herent, resembling clay, and may be cut and moulded to any shape. On drying it becomes hard, and a burnished surface takes a lustre like wax or pitch. In Holland, Friesland, Holstein, and Denmark, a so-called mud peat is " fished up " from the bottoms of ponds, as a black mud or paste, which on drying becomes hard and dense like the pitchy peat. The process of burning demonstrates that peat consists of two kinds of substances : one, the larger por- tion, is combustible, and is organic or vege- table matter ; the other, remaining indestruc- tible by fire, is mineral matter or ash. The combustible part of peat varies considerably in its proximate composition. It is an indefinite mixture of perhaps many compound bodies, the precise nature of which is unknown. They have received the collective names of huinus and geine, consisting of resinous and bitu- minous matters, crenic. apocrenic, ulmic, hu- mic, and geic acids, in combination with lime, magnesia, iron, and manganese, and forming ulmates, humates, &c., of these bases. While there is little doubt that other compounds ex- ist in peat, it appears to be certain that these are the chief constituents, to which it owes its peculiar properties. Below are tabulated analyses of some of these substances : CONSTITUENTS. Carbon. Hydrogen. Oxygen. Ulmic acid, artificial from sugar. Humic acid, from Frisian peat. . Crenic acid 67-10 61-10 56-47 4-20 4-30 2-74 28-70 84-60 40-78 45-70 4-80 49-50 In general we may say that the ripest and heaviest peat contains 10 or 12 per cent, more carbon and 10 or 12 per cent, less oxygen than the vegetable matter from which it is produced ; while between the unaltered vege- tation and the last stages of humification, the peat runs through an indefinite number of stages. The mineral part of peat, which re- mains as ashes, is variable in quantity and