Ice Making at Home 



Bv Jav F. Bancroft 



THERE is no sound 

 scientific reason why 

 a household refriger- 

 ating machine should not 

 be a commercial success and 

 go into very general use in 

 private homes. There is a 

 wide demand for such ma- 

 chines, and much money 

 and engineering skill have 

 been expended in their de- 

 velopment. Notwithstand- 

 ing this, it must be ad- 

 mitted that they have not 

 gone into use very exten- 

 sively in private house- 

 holds. 



The use of refrigeration 

 to cool and preserve our 

 food and drinks is so general 

 that it has now come to be 

 regarded as an essential 

 factor in our daily life. 

 Nevertheless it is surprising 

 how few users of such re- 

 frigeration there are who 

 could accurately explain 

 even the principles on 

 which the ice-cooled re- 

 frigerator works. Ev- 

 erybody knows that in 

 order to cool a sub- 

 stance it must be placed 

 in proximity to a cold 

 body, such as ice. There 

 are numerous ways in 

 which cold bodies can 

 be produced mechani- 

 cally, but the only way in practical use in 

 household refrigerators is by the evapora- 

 tion of a licjuid. If the hand is plunged 

 into warm water and then exposed to a 

 draft of air the hand dries, but also be- 

 comes very cool. This cooling effect 

 is more pronounced if ether or alcohol is 

 used instead of water, for such liquids 

 evaporate more readily. The cooling 

 effect is due to the fact that the liquid 

 has changed to a vapor, and in doing so 

 has absorbed a perceptible amount of 

 heat from the hand, which heat disap- 

 pears with the vapor. This principle is 



The re- 

 frigerat- 

 ing ap- 

 paratus 

 here de- 

 s cr ib ed 

 can be 

 conven- 

 iently lo- 

 cated in 

 the base- 

 ment be- 

 low the 

 kitchen. 

 The prin- 

 cipal fea- 

 ture of 

 this ma- 

 chine is 

 thedumb- 

 bell con- 

 t a i n e r 

 shown in 

 its relation to the 

 other parts of the 

 machine. This ma- 

 chine is 'so nearly 

 automatic that the 

 services of an expert 

 attendant are not 

 necessary 



extensively used in dry climates for cool- 

 ing water which is placed in porous- 

 walled vessels exposed to the air. The 

 small amount of water that seeps through 

 the porous walls and is evaporated will 

 cool down the remainder of the water 

 within the vessel. 



Should water be placed in a pan under 

 the receiver of an air-pump such water 

 can be very much cooled, or even con- 

 verted into ice, by removing the vapor 

 as fast as it is formed. Only a small 

 fraction of the liquid is evaporated, but 

 in the evaporation of this small fraction a 



891 



