334 Milk and Its Products 
may be less warmly built, still it is not sufficient 
that the superstructure be merely of siding nailed 
to the joists, leaving the inside bare. While, per- 
haps, it is not necessary that the outer siding be 
double, or that building paper be used upon the 
joists, still the joists should always be ceiled upon 
the inside and the ceiling neatly finished in oil. 
The construction of the curing room is the most 
important part of the cheese factory. Here the 
construction should be of such a nature that a 
fairly constant temperature may be maintained. This 
ean hardly be secured unless the building is covered 
on the outside with two thicknesses of boards, with 
paper between and tightly ceiled upon the inside. 
This part of the factory, at least, should always be 
upon a solid wall foundation. Constructed in this 
way, if care is taken to ventilate the building thor- 
oughly at night, and to close. it tight during the 
day time, a fairly cool curing room can be secured 
even during the hottest weather; but the temperature 
can be much more satisfactorily regulated if the ven- 
tilation comes through a sub-earth duct for a con- 
siderable distance. This may be arranged by laying 
a three or four-inch glazed sewer pipe at least four 
feet deep, from a point, on the surface fifteen or 
twenty rods from the building, and opening into 
the center of the curing room through the floor. 
If the’ mouth of this sub-earth duct can be placed 
in such a position that the prevailing winds will 
blow toward it, a circulation of cool air can more 
easily and certainly be secured. 
