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dust, that is the best, but it will do very well to pile it on a 

 thick layer of sawdust or even straw provided good drainage 

 is secured. (Not necessarily direct drainage, but, for instance, 

 a layer of gravel.) 



The walls (both inner and outer) should, to get the best 

 result, be made of matched boards and be two feet apart and 

 this space should be filled with closely packed insulating material. 

 The inner wall may be dispensed with and the insulating done 

 as the ice is piled up, but this will waste more material. 



Such a wall filled with dry sawdust or chaff will stop the 

 air circulation even better than a whole lot of board and paper 

 partitions and will, as a rule, be much cheaper in the country. 

 A series of air spaces allows circulation in each and unless there 

 are many of them the insulation will not be perfect, but they are 

 cleaner and not so apt to get damp and musty as the solid saw- 

 dust or chaff which every few years must be taken out and 

 dried. 



A combination of the two systems might possibly be the 

 best; say 12 or 18 inches solid in the center and an inch air space 

 on either side. 



The floor should slant toward the center so that the ice 

 will lean that way and not, in melting, press on the walls. It 

 is enough to cover the ice with a foot or so of the insulating 

 material, but above this free circulation of the air should be al- 

 lowed. If exposed to the sun it is a good thing to have a sort 

 of tent roof above the regular roof so as to provide shade. 



The value of various insulating material may be ranked in 

 the following order: cotton, husks of barley, wheat or oats, 

 leaves, chaff, husks of rice, wheat straw, sawdust and peat, all 

 losing value if not dry. 



Chaff, leaves and husks should not be used under the ice 

 in the bottom, as, when damp, they easily ferment and develop 

 heat 



As to the unavoidable loss during the year by melting in 

 the ice house, it is estimated that in December it amounts to 

 about 45 Ibs. for every square foot of the inside surface and 

 hence the percentage of loss is much greater in a small ice house 

 than in a larger one. 



Refrigerating machines have been hinted at before and 

 where a new creamery is built and where ice can not be se- 

 cured virtually at the door of the creamery, a refrigerating ma- 



