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THE POPULAR SCIENCE MONTHLY. 



was of an inch and a quarter internal diameter, and the lengths 

 were placed five inches apart. Through this coil the ammonia 

 circulated, the absorption system being used to effect the conge- 

 lation. 



The machines with which ice is made have also another and 

 up to the present time a larger application. This is the produc- 

 tion of cold in breweries, abattoirs, markets, and cold storage 



Fig 5. A Eoom in a Cold Storage Warehouse. 



houses. The fermentation of beer must take place at quite a low 

 temperature, which must be steadily maintained ; hence energetic 

 and continuous cooling of the wort has to be provided for. The 

 brewers were formerly among the largest customers of the ice 

 companies, but now nearly every brewery has a refrigerating ma- 

 chine of its own, and more machines are used by them than by 

 all other users put together. No ice is made with these machines, 

 except for packing beer for shipment, as the cooling required can 

 be accomplished more conveniently by circulating cold brine or 

 cold fresh water in pipes where it is needed. 



The system of cold storage which has sprung up within the 

 past few years has been made possible by this same process. Im- 

 mense quantities of meat and other perishable provisions are now 

 kept in great warehouses until wanted, thus insuring a steady 



