Читать книгу Rudimentary Treatise on the Construction of Locks онлайн

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The Germans, like the French, bestow great attention on their treatises relating to the manufacturing arts. Some of these are, indeed, worked up to a degree of minuteness which would seem superfluous, where little distinction is drawn between the importance of fundamental principles and that of mere technical details. Locks have had their due share. The article on locks in Prechtl’s Technological Encyclopædia written by Karmarsch, and published in 1842, occupies about 140 pages. Locks are very minutely classified by the author, according to their purposes and their modes of action, and are illustrated by many plates. One of his classifications is into German, French, and Bastard locks, referring in part to the extent to which the key turns round in the lock; and the last of the three having an intermediate character between the other two. After treating of the ordinary warded locks, he comes to the combination principle; and it is profitable here to notice, how well the works of our machinists are understood on the continent, when they have any thing to recommend them; there are a dozen closely printed pages devoted to a minute description of Bramah’s invention, with all the separate parts illustrated by copper-plate engravings. After this comes a more general account of the details and manufacture of locks, similarly illustrated by engravings.