TENTS. 15 



inclosed space which permits of economical use of chemicals with 

 greater uniformity of results. 



'instruction of tents. — The construction of the box covers such as 



'ested in the foregoing paragraph is a simple matter and con- 



, .xxcnt patterns will suggest themselves at once to anyone desirous 



of fumigating small trees. The framework should be light but well 



braced, and for a covering either 6^-ounce drill, painted to render it 



is nearly gas-tight as possible, or oilcloth is recommended. 



Prof. C. W. Woodworth, of the California experiment station, 

 gives the following directions for cutting the cloth for bell tents:" 



All of these tents are made in the same manner, and are the most economical in 

 cloth of any tents made. Commonly the tent is made by the "cut and fit" method. 

 These tents may be made with scarcely any loss, if cut according to the following 

 directions: Measure off strips of a length equal to twice the height plus one-tenth the 

 diameter of the tejit desired. These will make two strips each by marking the exact 

 middle and measuring off on one edge from the middle line one-quarter of the diameter 

 of the tent and on the other one-half the diameter. Now, take a long strip of molding 

 and bend it so as to touch these three points and mark off the curve so produced. 

 This allows for the seam. In making up, sew the two cut edges together in each pair 

 of strips. 



As has been stated, sheet tents, or more properly covers, are flat, 

 regular octagons. The dimensions are sometimes stated in terms of 

 the true diameter (i. e., the distance between opposite corners), 

 but for practical purposes the distance between parallel sides should 

 represent the size of the tent, for the reason that this represents 

 mthin about 2 feet (which must be allowed to rest on the ground) 

 the distance over the tallest tree that a given sheet can cover meas- 

 uring from the ground on one side to the ground on the other, over 

 the center of the tree. 



Hereafter in this bulletin the size of octagon covers as stated should 

 be understood to refer to the distance between parallel sides. The 

 specifications should be carefully worked out before beginning the 

 construction of a sheet tent as well as of other styles. First, the 

 dimensions of the tallest tree which the tent is required to cover 

 should be estimated. This may be accomplished by throwing a tape 

 attached to a reel over the top of the tree and measuring from ground 

 to ground. When covered, the weight of the tent will reduce the 

 extreme height of the tree ~in most cases by from 2 to 4 feet, 

 according to the weight of the tent and form of the tree. It will be 

 well to allow at least 4 feet of the tent to rest on the ground when 

 covering the largest tree. The desired size having been determined, 

 a diagram of an octagon should be constructed on paper, as indicated 

 in figure 1. Each side of the octagon when constructed will be 

 equal approximately to two-fifths of the distance between the parallel 



« Circular No. 11, Cal. Agr. Exp. Sta., pp. 9-10. 

 49918— Bull. 76—08 2 



