136 BULLETIN 414, U. S. DEPARTMENT OF AGEICULTUEE. 



they are much more expensive than wooden structures, somewhat 

 heavier, inconvenient to replace in case of breakage and deteriora- 

 tion, hot in summer and cold in winter. When made principally 

 of wood they are less expensive, much cooler in summer, lighter and 

 easier to move and handle, but subject to damage or destruction by 

 fire, more difficult to keep clean and free from vermin, and with 

 shorter lives than metal buildings. 



Whatever material be used in the construction, the following 

 desirable features should be embodied in the design: 



(1) The sections of which the building is composed should be of 

 such size as to permit convenient hauling and erecting. They 

 should not be too large for transportation on an ordinary wagon bed, 

 and in weight they should not exceed approximately 200 pounds, 

 the maximum weight which can be handled successfully by two men 

 in erecting and tearing down. 



(2) The sections should be so designed and the connections so made 

 as to secure the maximum of flexibility in the building and permit 

 ready reduction or increase in capacity to accommodate any number 

 of inmates. 



(3) All parts and sections should be constructed by template or 

 pattern, in order that similar parts may be absolutely interchange- 

 able. 



(4) All units should be so simple in design that they may be con- 

 structed by relatively inexperienced labor. Complicated joints, 

 irregular shapes, and difficult cuts should be avoided. 



(5) All the parts should be so-called stock articles or easy to impro- 

 vise, in order that the cost may be reduced to a minimum and that 

 renewals may be made with the greatest ease. 



Stock buildings of either metal or wood, embodying the above 

 desirable features, may be purchased from a number of manufac- 

 turers in various parts of the United States, or they may be very 

 readily constructed by the regular convict force under the leader- 

 ship and supervision of a good carpenter. The latter means probably 

 will appeal more strongly to prison officials, as the convict labor 

 usually is available for the work, and by employing it the buildings 

 can be constructed at a lower cost than they can be bought. 



For the assistance of communities in which it is desired to erect 

 buildings of this character, the Office of Public Roads and Rural 

 Engineering is prepared to furnish upon application complete de- 

 tailed plans and specifications of the portable building shown in 

 Plate X, figure 1, the general plans of which are given in Plate XI. 



In the preparation of these plans careful attention has been given 

 to all the featurres mentioned above as desirable. The sections are 

 designed for rapid erection of buildings 18 feet square, or, by pro- 



