Lightning Rod Protection
The answer to the old question: “Do lightprotect?” says the fire commisof Saskatchewan, in a recently issued C_____lar, must, in view of carefully compiled statistics, be in the affirmative, with a saving clause Attached, viz: that the installation of such rods must be thoroughly and efficien_____ done. Tlie circular says; Proper instalatkm, is the. only guarantee of protection. Hitherto, there has been much “scamping” of this feature and lightning rods have not protected. Result: Distrust and suspicion of s&ch systems in general. It may be interesting to. know the results of a careful investigation by Professor Day, Ontario Agriculture College, in this regard. In Ontario, in 1912 the efficiency of rods was found to be 94.5 per cent, and in 1913, 92 per cent. In Iowa an efficiency of 98.7 per cent, was shown and in Michigan an efficiency of per cent. These figures speak for themselves. That protection is afforded is undoubted bnt that the installation may give satisfactory results the following suggestions are submitted: Materials: Rods should be of soft drawn copper in the form of tape or stranded cable. Aluminum or galvanized iron may be used but copper has six times the conductivity of iron and is not corrosive. Aluminum may prove as durable as copper blit for the same size of wire its conductivity is only one-half that of copper. Grounding: Down to permanent moisture and in no case less than eight feet deep. A copper or steel groundplate is helpful. See that the grounding is not “scamped.” Location: Placing rods at diagonally opposite corners is best. Rods should run along ridge and in no case should come near interior piping, Cables should be protected from ground for6 or 8 feet up by nailing boards around them. Points: Chimneys and cupolas should haves separate points. Points should be from 20 to 30 feet apart. Metallic work: Roof, gutters; and all exterior metal work should be con-, nected with the cables or separately grounded. Metallic roof should be grounded at two orpreferably four corners. Do not use insulators for fastening cables. Farmers should ground all wire fences every 20 rods at least. A fence grounding should consist of a rod or wire connected with each lateral wire of the fence and extending at least 3 feet into the ground and projecting a few inches above the fence. These fence groundings should be made of same material as the fence wires, Many animals are killed annually through contact with underground fence wires iq thunderstorms.