236 



CANADIAN FARM YEAR BOOK. 



iperly Installed are almost a'bsolute 

 protection against lightning. 



Tihese practical results the farmers 

 of Canada can appreciate better than 

 scientific statements, and with these 

 at hand the Department can safely 

 recommend the rodding of farm build- 

 ings in accordance with directions 

 above given. 



The writer has omitted drawings 

 purporting to show how to rod ibuild- 

 ings. The proper method can only be 

 decided after a close examination of 

 eacih building in question, for then 

 alone can one intelligently apply the 

 principles already dealt with. 



For convenient reference the direc- 

 tions for proper rodding are repeated 

 without any of the explanations. 



1. Kind of rods. Material — Copper, 

 aluminum or galvanized iron, prefer- 

 ably the first because of durability. 

 Aluminum may prove equally durable. 

 Combinations are not advised, because 

 not as durable as single-metal rods. 

 Weight — Copper — ^At least 3 ounces 

 per foot. Aluminum — ^At least 2 1-4 

 ounces per foot. Steel (iron) — ^At 

 least 4 1-2 ounces per foot. Form — 

 Any form that will give durability and 

 convenience of installation. 



2. Ground connections. Depth — 

 Down to perpetual moisture. At least 

 8 feet deep. Number — On an oblong 

 ibuilding, at least two; on an Ir or T- 

 shaped building, at least three; on a 

 U-shaped building, at least four. LiO- 

 cation — Preferably at opposite comers, 

 though this may 'be modified to avoid 

 manure* or to go down near conductor- 

 pipe or other metallic portion of the 

 structure. If conductor-tpipe is on the 

 side of the building the ground rods 

 should be at the comers as above stat- 

 ed, the eave-troughs connected to it, 

 and then the conductor pipe also 

 grounded. Ground-rods sihould not be 

 (bimched, but should be distributed as 

 well as possible. Method — In deep soil 

 drill a hole at least eight feet deep and 

 run cable down. In shallow soil, at- 

 tach cable to metallic ground-plate, 

 which is put down as deep in soil as 

 possible; or run it into a well or a 

 stream or a crevice in the rock. If 

 none of these are feasible, put cable 

 as deep as possible and lay large, flat 

 stone over it. Caution — Be present. 



and see that ground-connectioag axe 

 properly made. The rest of the sys- 

 tem may be inspected at any time, but 

 the groimdings only when they are be- 

 ing put down, 



3. Systems. Hun cable from 

 ground up comer to eave, thence to 

 ridge, along ridge to other end, thence 

 down to eave, thence to other ground, 

 making a complete circuit. Ail cables 

 should be connected in one system. 

 No stuhs or dead ends sihould be left 

 ungrounded. Caution — ^Cables should 

 be protected from ground six or eight 

 feet up by nailing (boards around 

 them. 



4. Attachment. Fasten caJble to 

 'bam with nails, staples, clips or 

 metal "dispersers." Caution — ^Do not 

 use insulators. 



5. Points. Number— 20 to 30 feet 

 apart Location — On ridge, first onea 

 not over five feet from end; on or fb&- 

 side chimneys or cupolas; on dor- 

 mers; also on silos. Height — Four to 

 five feet, except those on or beside 

 chimneys, cupolas or similar promin- 

 ences; these must extend at l-east 

 eighteen inches above the highest 

 part. Form — Strong tubes, of same 

 weight and material as rods. 



6. Metallic Portions of (Structure. 

 RoofTgutters — Top connected to rod, 

 and bottom grounded. Eave-troughs 

 and conducto^^pipes — Free end of eave- 

 troughs connected to rod, and con- 

 ductor pipe grounded. Hay-fork 

 track — (Both ends connected to rod. 

 Tanks — Connected to rod above, 

 grounded below. Windmill — Connect- 

 ed to rod above, shaft grounded ibelow. 

 Metallic roof — Groxmded at two or foixr 

 corners, not from peak under any con- 

 sideration. Points should be used on 



the ridge and other prominences. 



7. Wire fences. In field — ^A ground- 

 ing at least every twenty rods. In 

 yards — At the four comers. At iboHd- 

 ing — Groimd at first post from build- 

 ing. Weight of groimdings^Equal to 

 three No. 12 or one No. 9 wire. How- 

 made — (Stapled on posts in contact 

 with all wires of fence, and extending 

 at least three feet in the ground, and 

 projecting above fence. 



8. Shade trees — Protect where 

 feasible. 



— OBuIL 220, Ont Dopt. Agrl. 



