Page:The American Cyclopædia (1879) Volume XIII.djvu/230

 220 PEAT PECAN two sizes of machines constructed, of the capa- city of 50 and 100 tons each of crude peat per day of ten hours. Mr. James Hodges of Mon- treal conceived the idea of a manufactory com- plete, which might be made to float about in the bog, excavating, pulping, manufacturing, and spreading out the pulped peat to dry. There are also the Elsberg, the Ashcroft and Betteley, Aubin's, and Haight's processes, and many others, all of which by different mechan- ical appliances accomplish the same result, the grinding and moulding of the peat, with sub- sequent drying, either in the open air or by artificial heat. Among the latest machines devised for this purpose is that of Thomas George Walker, which both grinds and artifi- cially dries the material. The wet peat, after being puddled in a pug-mill vat and heated by waste steam, is forced through the bottom into a box, whence it is blown by a steam jet through 400 ft. of 6-inch cast-iron pipe, coiled up in the furnace under the boiler, by which means it is thoroughly dried. It then passes through a larger pipe into a receiver, at the bottom of which it falls into a mould, where it is pressed into form by a plunger. The resid- ual steam and gases pass from the top of this receiver into a tank through another pipe, whose end is under water, in which any dust carried off by the steam is deposited ; and the waste steam and gases thus purified pass thence back to the pug-mill jacket, where they are used to heat the new material. A second tank, under the pug mill, receives the water from the waste steam condensed in the jacket, and all combustible gases rising to the top are conveyed through a pipe to the furnace and utilized as fuel. The successive heating of the peat in the pug-mill vat, and in the long pas- sage through the 6-inch pipe, so prepares it that it is easily moulded into a compact form as it leaves the receiver. A simple and effec- tual process for condensing peat has been in- vented by Mr. Franklin Dodge of Oswego, N. Y., which employs a cylindrical mill with per- forated disk triturators, placed in a scow and working in the bed. The peat is ground to a pulp, spread on a platform, and exposed to the air for a few days, when it is cut into blocks, turned, and afterward dried in cribs, which completes the process. Charcoal made from uncompressed peat excels in antiseptic and deodorizing properties. In Carinthia and Han- over the fresh peat is dried in kilns which are heated with the waste heat from certain metal- lurgical operations. In many European coun- tries peat is also charred in furnaces or kilns, and yields an exceedingly valuable coal, su- perior to wood charcoal. In S. E. Germany and Austria peat, both air- and kiln-dried, and peat charcoal are extensively used in met- allurgical operations, particularly in smelting iron. Peat has also been used to a limited extent in this country for the same purpose. The raw peat can only be used mixed with charcoal, on account of the water it contains. Distilled in an iron retort, and the volatile products passed through a red-hot iron tube in order to convert the paraffine and ingredients of the tar into gaseous hydrocarbons, 100 parts of peat have yielded, of porous charcoal or peat coke, 36 parts; ammoniacal liquor, 18*88; thick tar containing paraffine, 5*14; and illu- minating gas, 40. The illuminating power of the gas was equal only to that of seven can- dles, but the quantity obtained was at the rate of about 14,000 ft. per ton, which is aa much as is afforded by the best boghead cannel coal. When purified by passing through an alkaline mixture, it was found free from sulphur, and in this respect preferable to coal gas. The quali- ties of the coke are highly extolled ; and one of these being its freedom from sulphur, it is well adapted for the reduction of ores, in the treatment of which the presence of this ele- ment is highly objectionable. By destructive distillation peat affords a variety of useful pro- ducts, as pyroligneous acid or crude acetic acid, ammonia, volatile and heavy oils from which paraffine may be obtained, wood naphtha, in- flammable gases, charcoal, tar, &c. Extensive works for this purpose were established about 1850 in Ireland. The chief value of peat in the United States is likely to be for domestic purposes, although it has been used in some localities on locomotives and under steam boil- ers. It can be burned in open grates, close stoves, furnaces, ranges, and all the ordinary variety of heating apparatus in use in dwelling houses. Fibrous and easily crumbling, peat is usually burned upon a hearth, without a grate either in stoves or open fireplaces. Dense peat burns best upon a grate; the bars should be thin and near together, so that the air may reach every part of the fuel. (See COAL.) PECAN (Fr. pacanier a species of hickory (Gary a, olivceformis), abundant in the south- western states, and extending along rivers as far north as Illinois, but not known except in cultivation in the Atlantic states. Its botanical characters are similar to those in other species of the genus (see HICKOEY), but the leaflets are more distinctly stalked, and its sterile catkins are fasicled and form buds near the summit of the shoots of the preceding year, instead of being as in the other hickories upon a com- mon peduncle from the base of the shoot of the season ; the fruit is oblong with a thin husk ; the nut olive-shaped, from an inch to an inch and a half long, with four slight angles, yellowish brown, often with blackish lines; the shell very thin, containing an oily seed, which is sweet and edible, and by many per- sons preferred to any other nut. The tree is about 60 or 70 ft. high in the forests, but there is one at the Bartram estate near Philadelphia over 90 ft. ; the trunk is straight and well shaped, yielding a wood which, though coarse- grained, is heavy and durable. It appears to be long in coming into bearing, trees in France when 30 years old and 30 ft. high having borne no fruit ; old trees in the forest bear abundant-