Manufacture of Ice. 405 
The publication of this process has given occasion for a protest on 
part of Mr. Tichon, an apothecary of ere Bains nie according 
an 
taining ice, or a degree of cold corresponding thereto, the various appli- 
cations of which we speak would still be far from having received a prac- 
tical solution, but we already know of important services daily rendered 
to science by the apparatus of Carré which excited so much interest at 
the last London gaa ec sag we cannot here describe this interesting 
machine, for lack of r obliged to refer for particulars to 
“L’Année Scientifique ws ‘Tndustrelle, se Figuier, 1863, page 457, and 
Supplement, but the principle is as follows :—It is a based: upon the great 
quantity of heat which ammonia, liquefied by condensation, absor in 
becoming ae ousias as this Sods contains an immense amount of 
latent hea 
restate nia in the gaseous state is readily obtained as is well known, by 
boiling the ammoniacal liquid known in commerce as “ volatile alkali,” 
gether by ri aan the whol © perfectly shoe od without communica- 
tion with the outer air.- In the larger of these retorts we place a con- 
centrated solution of ammonia in water and heat it. Driven off by the 
heat, the gaseous ammonia cannot escape without becoming liquefied j in 
the small retort. But, when the apparatus is restored to the ordinary 
temperature, the liquefied ammonia reassumes its gaseous form and be- 
Two forms of apparatus are used, Ist, intermittent, 2d, Parga they 
are beginning to be introduced into various branches of industry. Brew- 
ers use them to freeze the wort of beer destined to undergo fermenta- 
uses to which this apparatus has been or can be app 
Mr. Carré started in this line of business in “the Peng place, by perfect- 
ing an apparatus of American invention, [that of Prof. A. C. Twining,| 
in which the volatilization of sulphuric ether served to produce a con- 
siderable degree of cold, and to obtain, in a short time, blocks of ice. 
