124 Economy of Machinery and Manufactures. 



his curiosity — but the power of steam comes to his assistance. Ink is rapidly sup- 

 plied to the moving types by the most perfect mechanism ; four attendants inces- 

 santly introduce the edges of large sheets of white paper to the junction of two great 

 rollers, which seem to devour them with unsated appetite ;— other rollers convey 

 them to the type already inked, and having brought them into rapid and successive 

 contact, redeliver them to four other assistants, completely printed, by an almost 

 momentary touch. Thus, in one hour, four thousand sheets of paper are printed on 

 one side ; and an impression of twelve thousand copies, from above three hundred 

 thousand movable pieces of metal, is produced for the public in six hours." 



This imperfect analysis has already transcended our prescribed 

 limits, but we cannot forbear from making one or two other quota- 

 tions. The description of the slide of Alpnach, although not new, 

 is very interesting, and may possibly lead to similar arrangements in 

 some of our own mountain forests. We will add, also, the account 

 of the bobbin-net manufacture, showing how cheaply an immense 

 quantity of any article can be supplied by the application of power, 

 guided by principles, such as have been enumerated and explained 

 in the work we have been examining. 



The slide of Alpnach is a surprising instance of a conquest gain- 

 ed over natural obstacles, by human enterprise, aided by mechanic- 

 al skill. 



The following description is quoted by Mr. Babbage from Dr. 

 Brewster's Journal, in which it appeared in 1819, translated from 

 Gilbert's Annalen. 



" For many centuries the rugged flanks and the deep gorges of Mount Pilatus, 

 in the Alps of Switzerland, were covered with impenetrable forests. Even the 

 daring hunters were scarcely able to reach them, and the inhabitants of the valley 

 had never conceived the idea of disturbing them with the axe. These immense 

 forests were therefore permitted to grow and to perish, without being of the least 

 utility to man, until a foreigner, conducted into their wild recesses in the pursuit of 

 the chamois, was struck with wonder at the sight, and directed the attention of sev- 

 eral Swiss gentlemen to the extent and superiority of the timber. The most intel- 

 ligent and skilful individuals, however, considered il quite impracticable to avail 

 themselves of such inaccessible stores. It was not until November, 1816, that M. 

 Rupp and three Swiss gentlemen, entertaining more sanguine hopes, drew up a 

 plan of a slide, founded on trigonometrical measurements. Having purchased a cer- 

 tain extent of the forests from the commune of Alpnach, they began the construc- 

 tion of the slide, and completed it in the spring of 181S. 



" The slide of Alpnach is formed entirely of about two hundred and fifty thousand 

 large pine trees, deprived of their bark, and united together in a very ingenious 

 manner, without the aid of iron. It occupied one hundred and sixty workmen, 

 during eighteen months, and cost nearly 100,000 franks, or £4,250. It is about 

 three leagues or forty four thousand English feet long, and terminates in the Lake 

 Lucerne. It has the form of a trough, about six feet broad, apd from three to six 

 feet deep. Its bottom is formed of three trees ; the middle one of which has a 

 groove cut in the direction of its length, for receiving small rills of water, which 

 are conducted into it from various places for the purpose of diminishing the friction. 



