130 
BULLETIN 414, U. S. DEPARTMENT OF AGRICULTURE. 
surfaces in such way as to proclaim rather than conceal the presence 
of dirt. 
Proper observance of the rules of ventilation and screening, given 
elsewhere, should be another common property of all structures for 
camp use. Attention to these features is a great aid toward assuring 
the health of the inmates. 
A measure of security commensurate with the requirements of the 
particular grades of convicts which they are designed to house should 
also be provided by all convict-camp structures. Buildings designed 
for the quartering of "honor convicts" may be relatively insecure, 
but the lower or more desperate characters must be held by the vari- 
ous means of bars and locks, chains and stockades. 
Finally, it is frequently desirable, in camps of variable population, 
to design the structures so as to allow ready reductions or increases 
in capacity. 
Fig. 7.— Wall tent. 
The foregoing are the principal properties which should be realized 
in all types of camp buildings. In order to indicate how these prop- 
erties may be embodied in such structures, the various types are 
hereafter discussed in detail, with plans, specifications, costs, and 
other available data given for a number of structures. 
TENTS. 
The form of tent used most extensively in connection with convict 
camps in the United States is the "wall tent" shown in figure 7. 
Such tents are supplied by the trade in various weights of cotton 
duck, designated according to the weight per yard, as 6 J, 8, 10, and 
12 ounce duck, the last-named weight being the heaviest goods in 
common use. Lightweight twills, measuring 30 inches in breadth 
and weighing from 6£ to 8 ounces per yard, are the materials usually 
employed in the construction of the largest sized tops, while 8, 10, 
and 12 ounce ducks are used in the smaller sizes. 
The door openings usually consist of flaps placed in the ends of the 
tent, though special side-opening tents also are obtainable. The 
