202 STATE BOARD OF AGRICULTURE. 



attached to the cupola or to the 4x4 post the points extend 30 inches 

 above the same. The upper end is tapered about 3 inches to a point, 

 this being done at the forge and finished with a coarse file. Threads 

 were cut at the lower ends of the 36'" points, the other lengths being 

 left unthreaded. 



POINTS FOR PROTECTION OF CHIMNEYS. 



It will be remembered that a heated column of air rising from a 

 chimney affords an easier path for lightning than the cooler surround- 

 ing medium. Then, too, the chimney is generally the highest part of 

 the building. Because of these facts, chimneys are struck more often 

 than any other one part of a building. The chimney on the implement 

 barn was protected in the following manner. The horizontal cable 

 which runs along the ridge of the barn was passed around the chimney 

 as indicated in Figure 1. On this cable was put a %'" galvanized iron 

 tee which was drilled and tapped in two of the ends at right angles 

 with each other for %'" set screws. A %" eyebolt, made by cutting off 

 the head of a common bolt and turning an eye on the end, was put 

 through the chimney four rows of brick from the top, and fastened 

 on the inside with a nut and washer. A piece of the y-V' cable was 

 used for the point, the upper end having four of the seven strands 

 spread outward and upward, the remaining three strands being twisted 

 together and standing vertically in the center of the four. After bend- 

 ing the point as shown in the drawing, the lower end was passed down 

 through the eye bolt and into the tee, and was firmly secured by one of 

 the %" set screws. The remaining set screw fastens the tee to the 

 horizontal cable. A short piece of heavy galvanized wire is shown in 

 the figure steadying the upper end of the point. 



METHOD OF SUPPORTING POINTS. 



The method used in putting up points is illustrated by No. 2 of 

 Figure 2. The %" rod is screwed into a i/^'" galvanized tee, (drilled 

 and tapped at the proper angle), and fastened to the roof by means of 

 a 10" piece of y-^" gas pipe screwed into the tee. The gas pipe was 

 prepared by first cutting threads on one end, then flattening the pipe on 

 the anvil, first heating the pipe to a white heat in the forge. Then 

 three y^' holes were drilled and countersunk for No. 10 wood screws. 

 The flattened pipe is bent to fit the ridge board and first row of shingles. 

 Care must be taken to drill and tap the tee at about the proper angle. 

 The size drill used is 25-64 inch, but a %'" or even a 13-32 drill will 

 do very well. The threads cut on the half-inch rod should fit those 

 tapped in the tee quite closely, and they should be just long enough 

 to allow the rod to be screwed firmly against the cable when it passes 

 through the tee. If the rod does not stand vertical after it is put up, 

 it can easily be made so by bending the flattened pipe or by driving 

 a staple close to the tee and on the side you wish the point tipped; 

 and if this does not make the rod set vertical, it can be made so by 

 pulling the upper end of the point in the direction you wish it to go, 

 and striking the rod on that side close to the tee. 



