76 ANNUAL OF SCIENTIFIC DISCOVERY. 



of water being as clearly seen as on the surface. We see no reason 

 why it could not be used with advantage in the rivers and bays of the 

 United States. 



CORKS MANUFACTURED BY MACHINERY. 



AMONG the articles exhibited at the display, just closed, of French 

 domestic products, we remarked corks for bottles, which were made 

 by machinery. Numerous and costly experiments, to supersede man- 

 ual labor, had entirely failed. But Messrs. Duprat and Co., of Cas- 

 tres, devised and executed an apparatus, by which, at their great 

 manufactory of corks, they turned out a hundred thousand daily, of 

 the best formation and finish, easily to be -distinguished from those of 

 handicraft in common use. By multiplying the machines, the manu- 

 facturers could meet any amount of demand. Hitherto, for the essen- 

 tial operation, the rounding, workmen of special skill and prac- 

 tice were indispensable, and received wages of four francs per diem 

 for the thousand corks they were able to furnish. By the machine 

 called La Tourneuse, plied with little fatigue, by a woman or child, 

 the supply is 25,000 per day. French Journal 



ICE MADE BY MECHANICAL POWER. 



REPORTS have been circulating, for some time past, of an invention 

 for manufacturing ice by some mechanical means; but the idea has 

 met with almost universal ridicule, so that we were very much sur- 

 prised, a short time since, when a friend from the South informed us 

 that there is a company now in existence in New Orleans, who pro- 

 pose to manufacture ice ; and he further informed us that he had seen 

 beautifully clear lumps, four feet square, manufactured by the compa- 

 ny. He added, that, even if they failed in making ice in large quan- 

 tities, there was no doubt but that they could produce currents of very 

 cold air, which could be introduced into dwellings in summer, for the 

 purpose of cooling them, and preventing disease. 



We find in a late number of the Scientific American a letter from 

 New Orleans, in which the manner of proceeding is partially detailed. 

 The writer says, that the invention is not purely mechanical, but is 

 based upon both mechanics and chemistry. It consists essentially of 

 a force-pump, in which air is divested of latent heat by mechanical 

 compression, and an engine, in which the same air is made to act ex- 

 pansively, and in the process to absorb from the water to be frozen 

 the heat due to its increase of volume. But there are several auxil- 

 iary agents for giving this simple contrivance its greatest effective utili- 

 ty. Thus, by an obvious arrangement of attaching the pump and en- 

 gine to the opposite ends of a common beam, the power consumed in 

 condensing the air in the pump is, to a considerable degree, recovered in 

 its expansion in the engine. At the same time, the heat evolved by 

 the compression of the air is extinguished by a jet of water, thrown in- 

 to the body of the force-pump by means of a smaller pump ; while 

 the heat necessary to impart to the expanding air the elasticity and me- 



