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قراءة كتاب Popular Technology; or, Professions and Trades. Vol. 1 (of 2)

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‏اللغة: English
Popular Technology; or, Professions and Trades. Vol. 1 (of 2)

Popular Technology; or, Professions and Trades. Vol. 1 (of 2)

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دار النشر: Project Gutenberg
الصفحة رقم: 6

upright position over a cistern, and pierced in the bottom in several places. The holes being partially stopped with canes, the part which still remains in the form of syrup, filters through them into the cistern beneath, while the rest is left in the form of sugar, in the state called muscovado.

40. This sugar is of a yellow colour, being yet in a crude, or raw state. It is further purified by various processes, such as redissolving it in water, and again boiling it with lime and bullocks' blood, or with animal charcoal, and passing the syrup through several canvas filters.

41. Loaf-sugar is manufactured by pouring the syrup, after it has been purified, and reduced to a certain thickness by evaporation, into unglazed earthen vessels of a conical shape. The cones have a hole at their apex, through which may filter the syrup which separates from the sugar above. Most of the sugar is imported in a raw or crude state, and is afterward refined in the cities in sugar-houses.

42. Molasses is far less free from extraneous substances than sugar, as it is nothing more than the drainings from the latter. Rum is distilled from inferior molasses, and other saccharine matter of the cane, which will answer for no other purpose.

43. Sugar is also manufactured from the sap of the sugar-maple, in considerable quantities, in the northern parts of the United States, and in the Canadas. The sap is obtained by cutting a notch, or boring a hole, in the tree, and applying a spout to conduct it to a receiver, which is either a rude trough, or a cheap vessel made by a cooper. This operation is performed late in the winter, or early in the spring, when the weather is freezing at night, and thawing in the day.

44. The liquid in which the saccharine matter is suspended, is evaporated by heat, as in the case of the juice of the cane. During the process of evaporation, slices of pork are kept in the kettle, to prevent the sap or syrup from boiling over.

45. When a sufficient quantity of syrup, of a certain thickness, has been obtained, it is passed through a strainer, and, having been again placed over the fire, it is clarified with eggs and milk, the scum, as it rises, being carefully removed with a skimmer. When sufficiently reduced, it is usually poured into tin pans, or basins, in which, as it cools, it consolidates into hard cakes of sugar.

46. Most of the lands in a state of nature, are covered with forest trees. This is especially the case in North America. When this division of our continent was first visited by Europeans, it was nearly one vast wilderness, throughout its entire extent; and even now, after a lapse of three centuries, a great portion of it remains in the same condition. The industrious settlers, however, are rapidly clearing away the natural encumbrances of the soil; and, before a similar period shall have passed away, we may expect, that civilized men will have occupied every portion of this vast territory, which may be worthy of cultivation.

47. The mode of clearing land, as it is termed, varies in different parts of the United States. In Pennsylvania, and in neighborhoods settled by people from that state, the large trees are deadened by girdling them, and the small ones, together with the underbrush, are felled and burned. This mode is very objectionable, for the reason, that the limbs on the standing trees, when they have become rotten, sometimes peril the lives of persons and animals underneath. It seems, however, that those who pursue this method, prefer risking life in this way to wearing it out in wielding the axe, and in rolling logs.

48. A very different plan is pursued by settlers from New-England. The underbrush is first cut down, and piled in heaps. The large trees are then felled, to serve as foundations for log-heaps; and the smaller ones are cut so as to fall as nearly parallel to these as practicable. The smaller trees, as well as the limbs of the larger ones, are cut into lengths of twelve or fifteen feet.

49. At a proper season of the year, when the brush has become dry enough, fire is applied, which consumes much of the small stuff. The logs are next hauled together with oxen or horses, and rolled into heaps with handspikes. The small stuff which has escaped the first burning, is thrown upon the heaps, and, fire being applied, the whole is consumed together.

50. In the Northern, Middle, and Western states, where a great proportion of the timber is beech, maple, and elm, great quantities of ashes are obtained in this mode of clearing land. From these ashes are extracted the pot and pearl ashes of commerce, which have been, and which still are, among the principal exports of the United States.

51. The usual process of making potash is as follows: the crude ashes are put into large tubs, or leeches, with a small quantity of salt and lime. The strength of this mixture is extracted by pouring upon it hot water, which passes through it into a reservoir. The water thus saturated is called black ley, which is evaporated in large kettles. The residuum is called black salts, which are converted into potash by applying to the kettle an intense heat.

52. The process of making pearlash is the same, until the ley has been reduced to black salts, except that no lime or salt is used. The salts are baked in large ovens, heated by a blazing fire, which proceeds from an arch below. Having been thus scorched, the salts are dissolved in hot water. The solution is allowed to be at rest, until all extraneous substances have settled to the bottom, when it is drawn off and evaporated as before. The residuum is called white salts. Another baking, like the former, completes the process.

53. Very few of the settlers have an ashery, as it is called, in which the whole process of making either pot or pearl ash is performed. They usually sell the black salts to the store-keepers in their neighborhood, who complete the process of the manufacture.

54. The trade in ashes is often profitable to the settlers; some of them even pay, in this way, the whole expense of clearing their land. Pot and pearl ashes are packed in strong barrels, and sent to the cities, where, previous to sale, they are inspected, and branded according to their quality.



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