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PEAT (possibly connected with Med. La...

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Originally appearing in Volume V21, Page 32 of the 1911 Encyclopedia Britannica.
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PEAT (possibly connected with Med. See also:Lat. petia, pecia, piece, ultimately of See also:Celtic origin; cf. O. See also:Celt. pet, O. Ir. See also:pit, Welsh peth, portion) , a product of decayed vegetation found in the See also:form of bogs in many parts of the See also:world. The See also:continent of See also:Europe is estimated to contain 212,700 sq. m. of See also:bog; See also:Ireland has 2,858,150 acres, See also:Canada 30,000,000 acres, and the See also:United States 20,000,000 acres. The See also:plants which give origin to these deposits are mainly aquatic, including reeds, rushes, sedges and mosses. Sphagnum is See also:present in most peats, but in Irish peat Tlzacomitrum lanuginosum predominates. It seems that the disintegration of the See also:vegetable tissues is effected partly by moist atmospheric oxidation and partly by anaerobic bacteria, yeasts, moulds and See also:fungi, in depressions containing fairly still but not stagnant See also:water, which is retained by an impervious See also:bed or underlying strata. As decomposition proceeds the products become waterlogged and sink to the bottom of the See also:pool; in the course of See also:time the deposits attain a considerable thickness, and the See also:lower layers, under the superincumbent pressure of the water and later deposits, are gradually compressed and carbonized. The most favourable conditions appear to be a moist See also:atmosphere, and a mean See also:annual temperature of about 450 F.; no bogs are found between latitudes 45° N. and 450 S. Peat varies from a See also:pale yellow or See also:brown fibrous substance, resembling See also:turf or compressed See also:hay, containing conspicuous plant PECAUT 31 remains, to a compact dark brown material, resembling See also:black See also:clay when wet, and some varieties of See also:lignite when dry.

Two typical forms may be noticed: " See also:

Hill peat " (the See also:mountain or brown bogs of Ireland), found in mountainous districts, and consisting mainly of Sphagnum and See also:Andromeda; and " Bottom peat " (the See also:lowland or red bogs of Ireland), found in lakes, See also:rivers, and See also:brooks, and containing Hypnum. It always contains much water, up to 90%, which it is necessary to remove before the product can be efficiently employed as a See also:fuel, and for most other purposes. A specimen dried at See also:loo C. had the See also:composition: See also:carbon =60.48%, See also:hydrogen = 6.1o%, See also:oxygen=32.55%, See also:nitrogen= o.88%, ash=3.30%; the ash is very variable—from 1 to 65 %and consists principally of clay and See also:sand, with lesser amounts of ferric See also:oxide, See also:lime, See also:magnesia, &c. The specific gravity has been variously given, owing to the variable water content and See also:air spaces; when dried and compressed, however, it is denser than water. Peat-winning presents certain See also:special features. The See also:general practice is to cut a See also:trench about a See also:foot deep with a peculiarly shaped See also:spade, termed in Ireland a " slane," and remove sods from 3 to 4 ft. See also:long. When one layer has been removed, the next is attacked, and so on. If the See also:deposit be more solid step-working may be adopted, and should water be reached recourse may be had to long-handled slanes. The sods are allowed to drain, and then stacked for drying in the air, being occasionally turned so as to dry equally; this See also:process may require about six See also:weeks. The dried sods are known as " dug peat." Excavators and dredges are now extehsively used, and the drying is effected in heated See also:chambers, both fixed and revolving. The See also:low value of See also:ordinary dug peat as a fuel has led to processes for obtaining a more useful product. In M.

Ekenberg's process the wet peat is pulped and milled so as to make it of See also:

uniform composition, and the pulp passed into an See also:oven maintained at 180°–200° F., where it is carbonized by superheated water. The pressed product, which resembles lignite, still contains 8 to 14% of water; this is driven off by See also:heat, and the See also:residue briquetted. The final product is nearly equal to See also:coal in calorific value, and has the additional See also:advantage of a lower See also:sulphur content–0.g to 0.4 0/0 against about 2 % in ordinary coal. M. Zeigler's method leads to the See also:production of a useful See also:coke. Both these processes permit the recovery of valuable by-products, especially ammonium sulphate. Experiments for obtaining a See also:gas suitable for See also:consumption in gas-engines have been followed by commercial processes devised by the See also:Mond Gas See also:Corporation, See also:London, and Crossley Bros. of See also:Manchester, and by See also:Caro and See also:Frank in See also:Germany. The processes essentially consist in destructively distilling peat in special retorts and under specified conditions, and, in addition to the gas, there is recovered a useful coke and also the nitrogen as ammonium sulphate. The See also:conversion of the nitrogen into See also:ammonia has been the subject of much See also:work, and is commercially pursued at a See also:works at Carnlough, Co. See also:Antrim, under See also:patents held by H. C. Woltereck.

The peat is treated with a mixture of air and water vapour in special furnaces, and the gaseous products, including See also:

paraffin See also:tar, acetic See also:acid and ammonia, are led through a special scrubber to remove the tar, then through a See also:tower containing See also:milk of lime to absorb the acid (the See also:calcium acetate formed being employed for the manufacture of See also:acetone, &c.), and finally through a sulphuric acid tower, where the ammonia is converted into ammonium sulphate which is recovered by See also:crystallization. Peat has also been exploited as a source of commercial See also:alcohol, to be employed in See also:motors. In the process founded on the experiments of R. W. See also:Wallace and See also:Sir W. See also:Ramsay, which gives 25 to 26 gallons of spirit from a ton of peat, the peat is boiled with water containing a little sulphuric acid, the product neutralized with lime and then distilled; the ammonia is also recovered. In another process a yield of 4o gallons of spirit and 66 lb of ammonium sulphate per ton of peat is claimed. Of other applications we may See also:notice C. E. See also:Nelson's process for making a See also:paper, said to be better than ordinary wrapping; the first factory to exploit this See also:idea was opened at Capac, See also:Michigan, in 1906. Peat has been employed as a manure for many years, and recently attempts have been made to convert artificially its nitrogen into assimilable nitrates; such a process was patented by A. Mtintz and A.

G. See also:

Girard of See also:Paris, in 1907. See P. R. Bjorling and F. T. See also:Gissing, Peat and its Manufacture (1907) ; F. T. Gissing, Commercial Peat (1909) ; E. Nystrom, Peat and Lignite (1908), published by See also:Department of Mines of Canada. P$CAUT, See also:FELIX (1828-1898), See also:French educationalist, a member of an old Huguenot See also:family, was See also:born at Salies de See also:Beam, in 1828. He was for some months evangelical pastor at Salies, but he had no pretence of sympathy with ecclesiastical authority He was consequently compelled to resign his pastorate, and for some years occupied himself by urging the claims of a liberal See also:Christianity.

In 1879 he conducted a general inspection of See also:

primary See also:education for the French See also:government, and several similar See also:missions followed. His fame chiefly rests in his successful organization of the training school for See also:women teachers at See also:Fontenoy-aux-See also:Roses, to which he devoted fifteen years of ceaseless toil. He died on the 31st of See also:July 1898. A See also:summary of his educational views is given in his Public Education and See also:National See also:Life (1897).

End of Article: PEAT (possibly connected with Med. Lat. petia, pecia, piece, ultimately of Celtic origin; cf. O. Celt. pet, O. Ir. pit, Welsh peth, portion)

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