BUREAU OF PUBLIC EOADS. 501 



part of the time of the limited technical force available. It is a 

 service that is of great value to the more or less isolated farmer who 

 is without other means of securing information and to the many who 

 do not know where to look even though other sources of information 

 are accessible to them. 



Much of the structural and mechanical engineering work of the 

 year has been done in cooperation with or at the request of other 

 bureaus of the department whose findings affect farm structures, 

 machinery or equipment, and which for proper presentation require 

 designs, either in the form of blue prints or as dlustrations accompany- 

 ing text matter. A num.ber of farm structure and equipment designs 

 were prepared for general distribution. 



Plans of buildings to house the experimental and investigational 

 work of other bureaus were prepared and a study was made for the 

 purpose of enlarging the water supply at the Arlington Experimental 

 Farm, and plans are also in preparation for a new heating and power 

 plant for the farm. 



One of the most important investigations conducted during the 

 year is that which relates to the ventilation of barns, a project which 

 was carried on in cooperation with the American vSociety of Agricul- 

 tural Engineers. This matter of ventilation, so important to the 

 maintenance of the health of stock, has not heretofore received the 

 amount of scientific study its importance justifies. Very little precise 

 information has been available with regard to the effect of temperature 

 and wind upon the operation of a ventilation system, and the lack 

 of such information has been responsible for a large percentage of 

 expensive failures. The bureau's studies, which are still incomplete, 

 have already supplied scientific data of great value to ventilating 

 engineers, and a progress report in the form of a department bulletin 

 has been prepared for publication. 



Owing to the numerous inquiries regarding the construction of 

 farm dams and the development of farm hydroelectric power plants, 

 arrangements were made with the agricultural engineering depart- 

 ment of the Virginia Polytechnic Institute for a cooperative investi- 

 gation with a view to the publication of a bulletin which will bring 

 home to many farmer o^^^le^s of potential water power the energy 

 that is going to waste and enable them to determine for themselves 

 U an installation is practical, the power to be derived, and a rough 

 estimate of the cost. 



The text of a bulletin discussing the mstallation of multipipe 

 warm air furnaces was practically completed. As one of a series 

 of publications pertainino; to farmhouse heating it should be of 

 considerable interest to farmers confronted with a house-heating 

 problem. 



Concrete is almost universally used on the farm, and while some- 

 thing is generally known about its mixing, it is not always that a sat- 

 isfactory or economical concrete is secured. This has been c^uite 

 generally realized, as indicated by requests for information. Farmers' 

 Bulletin 1279, Plam Concrete for Farm Use, is now in the hands of 

 the printer and deals with the general principles of making, placing 

 and caring for plain concrete. This is the first of a contemplated 

 series dealing with concrete construction on the farm. 



