76 Progress of Invention. 



of power. • As there is no vibration, and the shuttle is thrown 

 with mathematical accuracy, the cloth, even when viewed in the 

 microscope, is found to be entirely free from those irregularities 

 and imperfections which in the ordinary kinds are concealed by 

 the dressing. The atmosphere, instead of being heated and cor- 

 rupted, is cooled and purified hy innumerable jets of fresh air. 

 "With the ordinary power-loom, the shuttle is thrown only about 

 180 times in a minute ; with the pneumatic arrangement, it is 

 thrown at least 240 times. This increase of velocity, accom- 

 panied by the fact that when condensed air is used the thread 

 almost never breaks, will immensely augment the annual pro- 

 duction. Supposing that the half million of looms which are in 

 operation in the United Kingdom were on the pneumatic principle, 

 the increase of production would, on a moderate calculation, be at 

 least a million and a half yards per annum. The new loom has a 

 great advantage over the old, as to first cost and the expense arising 

 from wear and tear. ]N o less than thirty-eight parts hitherto indis- 

 pensable are got rid of, and friction is greatly lessened in various 

 ways. Oil not being required, there is no danger of the cloth being 

 stained. The fibres, which greatly impede the motion of the shuttle 

 in the old loom, are blown away in the new. The movement of the 

 shuttle is effected in a very simple way. Air is condensed into a 

 reservoir by the steam-engine, and conveyed under the floor in 

 pipes, which communicate with flexible tubes that transmit it to 

 each loom ; or the loom itself condenses the air it requires by means 

 of a small air-pump, or even a bellows. A pinion on the main axle 

 of the loom causes the revolution of a wheel, upon which is fixed an 

 inclined stud that acts upon a lever which opens a valve. The latter 

 lets out a jet of air that blows the shuttle forward with great 

 velocity and unerring accuracy. Of course there is a separate 

 valve, lever, etc., for each of the directions in which the shuttle is 

 to be thrown. The superiority of the new loom to others previously 

 invented has, however, been denied. ' 



The Musical Clock oe St. Gekmain l'Atjxeeeois, at Pabis. 

 — This is another very interesting application of compressed air to 

 the simplification of mechanism. All who hear for the first time 

 the musical clocks of Bruges, Mechlin, etc., are charmed with them ; 

 but when the same piece, however elaborate it may be, is heard 

 again and again, the admiration cools, until at last, to those who 

 are condemned to listen to it, year after year, from infancy to age, 

 it must become little less than an annoyance. Tet when we con- 

 sider that each tune played by a musical clock requires a barrel or 

 cylinder, which costs a very large sum — that used in the clock at 

 Bruges cost 60,000 francs — we must readily admit that those who 

 for the credit of their city are desirous of having a musical clock, 

 must make up their minds to the endless repetition of the same 

 piece of music. The mechanician charged with the construction of 

 the clock of St. Germain l'Auxerrois, to which forty bells are 

 attached, appears, however, to have removed this difficulty, since he 

 has lowered the price of the barrel from 60,000 to 250 francs, which 

 makes it possible, withoutgreat expense, frequently to change the tune. 



