DAIRYING 105 



The floor should be insulated as well as the walls and ceiling. 

 Ruddick, of Canada, made extensive experiments with various 

 kinds of floor construction, including the use of hollow brick, 

 concrete blocks, etc., and got satisfactory results from a floor 

 built as follows: A four-inch layer of concrete covered with 

 eight inches of cinders, on top of which is placed tar paper, and 

 above the paper a two-inch finishing coat of concrete. The tar 

 paper prevents the wet concrete from filling the air spaces in the 

 cinders and spoiling the insulating effect of the cinders. Some 

 other material than tar paper, like roofing pitch, may be spread 

 over the first coating of concrete. The cinders must be kept dry 

 and thus make them an effective insulating layer. A sufficient 

 slope should be given to the floor to drain it, and the opening 

 to the drain provided with a trap to keep out currents of air. 



THE FLOOR OF AN ICE STORAGE HOUSE. 



854. The floor of an ice storage house must be well drained 

 so as to carry away any water from the melting ice. A layer of 

 gravel on top of this drained area can be covered with sawdust 

 ten inches or more deep, and the ice blocks packed close together 

 on this dry sawdust. No sawdust should be allowed to get in be- 

 tween the cakes of ice. The walls of the ice storage room should 

 extend into the ground far enough to prevent circulation of air 

 under the foundation, and a coating of pitch or waterproofing 

 placed on the outside of this wall, especially below the surface of 

 the ground. 



THE WALLS OF THE ICE STORAGE BUILDING. 



855. The outside walls can be built of lumber, brick, con- 

 crete, or cement blocks. All these materials should be given a 

 coating of waterproofing material, either paint, pitch or paraffin, 

 in order to prevent the absorption of moisture which makes the 

 walls a good conductor of heat and reduces the insulating 

 efficiency. If a waterproof covering is not used the inside of 



