A History of Inventions, Discoveries, and Origins. Johann Beckmann

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СКАЧАТЬ determined the question in favour of the church430. In the year 1332, one Bartolomeo Verde proposed to the Venetians to build a wind-mill. When his plan had been examined, a piece of ground was assigned to him, which he was to retain in case his undertaking should succeed within a time specified431. In the year 1393, the city of Spires caused a wind-mill to be erected, and sent to the Netherlands for a person acquainted with the method of grinding by it432. A wind-mill was also constructed at Frankfort in 1442, but I do not know whether there had not been such there before.

To turn the mill to the wind, two methods have been invented. The whole building is constructed in such a manner as to turn on a post below, or the roof alone, together with the axle-tree, and the wings are moveable. Mills of the former kind are called German-mills, those of the latter Dutch. They are both moved round either by a wheel and pinion within, or by a long lever without433. I am inclined to believe that the German-mills are older than the Dutch; for the earliest descriptions which I can remember, speak only of the former. Cardan434, in whose time wind-mills were very common both in France and Italy, makes however no mention of the latter; and the Dutch themselves affirm, that the mode of building with a moveable roof was first found out by a Fleming in the middle of the sixteenth century435. Those mills, by which in Holland the water is drawn up and thrown off from the land, one of which was built at Alkmaar in 1408, another at Schoonhoven in 1450, and a third at Enkhuisen in 1452, were at first driven by horses, and afterwards by wind. But as these mills were immoveable, and could work only when the wind was in one quarter, they were afterwards placed not on the ground, but on a float which could be moved round in such a manner that the mill should catch every wind436. This method gave rise perhaps to the invention of moveable mills.

It is highly probable, that in the early ages men were satisfied with only grinding their corn, and that in the course of time they fell upon the invention of separating the meal from the pollard or bran. This was at first done by a sieve moved with the hands; and even yet in France, when what is called mouture en grosse is employed, there is a particular place for bolting, where the sieve is moved with the hand by means of a handle. It is customary also in many parts of Lower Saxony and Alsace, to bolt the flour separately; for which purpose various sieves are necessary. The Romans had two principal kinds, cribra excussoria and pollinaria, the latter of which gave the finest flour, called pollen. Sieves of horse-hair were first made by the Gauls, and those of linen by the Spaniards437. The method of applying a sieve in the form of an extended bag to the works of the mill, that the meal might fall into it as it came from the stones, and of causing it to be turned and shaken by the machinery, was first made known in the beginning of the sixteenth century, as we are expressly told in several ancient chronicles438.

This invention gave rise to an employment which at present maintains a great many people; I mean that of preparing bolting-cloths, or those kinds of cloth through which meal is sifted in mills. As this cloth is universally used, a considerable quantity of it is consumed. For one bolting-cloth, five yards are required; we may allow, therefore, twenty-five to each mill in the course of a year. When this is considered, it will not appear improbable, that the electorate of Saxony, according to a calculation made towards the end of the seventeenth century, when manufactories of this cloth were established, paid for it yearly to foreigners from twelve to fifteen thousand rix-dollars. That kind of bolting-cloth also which is used for a variety of needle-work, for young ladies’ samplers, and for filling up the frames of window-screens, &c., is wove after the manner of gauze, of fine-spun woollen yarn. One might imagine that this manufacture could not be attended with any difficulty; yet it requires many ingenious operations which the Germans cannot easily perform, and with which they are, perhaps, not yet perfectly acquainted. However this may be, large quantities of bolting-cloth are imported from England. It indeed costs half as much again per yard as the German cloth, but it lasts much longer. A bolting-cloth of English manufacture will continue good three months, but one of German will last scarcely three weeks. The wool necessary for making this cloth must be long, well-washed, and spun to a fine equal thread, which, before it is scoured, must be scalded in hot water to prevent it from shrinking. The web must be stiffened; and in this the English have an advantage we have not yet been able to attain. Their bolting-cloth is stiffer as well as smoother, and lets the flour much better through it than ours, which is either very little or not at all stiffened. The places where this cloth is made are also not numerous. A manufactory of it was established at Ostra, near Dresden, by Daniel Kraft, about the end of the seventeenth century; and to raise him a capital for carrying it on, every mill was obliged to pay him a dollar. Hartau, near Zittau, is indebted for its manufactory to Daniel Plessky, a linen-weaver of the latter, who learned the art of making bolting-cloth in Hungary, when on a visit to his relations, and was enabled to carry it on by the assistance of a schoolmaster named Strietzel. Since that period this business has been continued there, and become common439. The cloth which is sent for sale, not only everywhere around the country, but also to Bohemia, Moravia, and Silesia, is wove in pieces. Each piece contains from sixty-four to sixty-five Leipsic ells: the narrowest is ten, and the widest fourteen inches in breadth. A piece of the former costs at present from four to about four dollars and a half, and one of the latter six dollars. This cloth, it must be allowed, is not very white; but it is not liable to spoil by lying in warehouses. Large quantities of bolting-cloth are made also by a company in the duchy of Wurtemberg. At what time this art was introduced there I cannot say; for every thing I know of it I am indebted to a friend, who collected for me the following information in his return through that country. The cloth is not wove in a manufactory, but by eighteen or twenty master weavers, under the inspection of a company who pay them, and who supply all the materials. The company alone has the privilege of dealing in this cloth; and the millers must purchase from their agents whatever quantity they have occasion for440. The millers however choose rather, if they can, to supply themselves privately with foreign and other home-made bolting-cloth, as they complain that the weavers engaged by the company do not bestow sufficient care to render their cloth durable: besides, the persons employed to carry about this cloth for sale, often purchase secretly cloth of an inferior quality in other places, and sell it as that of the company. Bolting-cloth is made also at Gera, as well as at Potsdam and Berlin; at the latter of which there is a manufactory of it carried on by the Jews.

For some years past the French have so much extolled a manner of grinding called mouture économique, that one might almost consider it as a new invention, which ought to form an epoch in the history of the miller’s art. This art, which however is not new, consists in not grinding the flour so fine at once as one may wish, and in putting the meal afterwards several times through the mill, and sifting it through various sieves. This method, which in reality has nothing in it either very ingenious or uncommon, was known to the ancient Romans, as we may conclude from the account of Pliny, who names the different kinds of meal, such as similago, simila, flos, pollen, cibarium, &c.; for these words are not synonymous, but express clearly all the various kinds of meal or flour which were procured from the same corn by repeated grinding and sifting. In general, the Romans had advanced very far in this art441; and they knew how to prepare from corn more kinds of meal, and from meal more kinds of bread, than the French have hitherto been able to obtain. Pliny reckons that bread should be one-third heavier than the meal used for baking it; and that this was the proportion in Germany above a hundred years ago, is known from experiments on bread made at different times, which, however uncertain they may always have been, give undoubtedly more СКАЧАТЬ