16 



BULLETIN" 1U, U. S. DEPARTMENT OF AGRICULTURE. 



ground to the top of tank is required. If built entirely above the 

 ground a complete outside form is necessary. After the outside 

 forms are in place pour 4 inches of concrete in the bottom. On this 

 concrete set the inside form, leaving a space of from 2 to 4 inches 

 between the forms, depending on the thickness of the outside wall. 

 After the concrete is set remove the inside form and coat the inside 

 walls and floor with hot asphalt or tar. The sheets of insulation 

 should be coated also with the same material and put in place on the 

 floor and against the walls, care being taken to make all joints tight. 

 After the insulation is in place cut down the inside form, previously 

 used, to a size that will provide a 4-inch space between the walls and 



Fig. 12. — Arrangement of concrete-insulated cooling tank built partly below ground level. 



forms. The form should bo set in place and blocked up 4 inches 

 above the floor, and the concrete for the inner walls and floor should 

 be poured in one operation. The wooden curb around the top of the 

 tank should have 20-penny spikes driven into the underside at fre- 

 quent intervals and the curb set in place and pressed down so as to 

 embed the spikes in the concrete before it sets. If the inner surface 

 of the walls is rough upon removal of the forms, a plaster coat ol 

 cement mortar should be applied. 



DIVIDING THE TANK INTO A SMALL AND A LARGE COMPARTMENT. 



The size of the tank depends upon the quantity of milk to b< 

 cooled. Frequently tanks are built of such. sizes as to require an ex 



