198 STATE BOARD OF AGRICULTURE. 



joint, besides being well cleaned, screwed, scarfed, or riveted, should 

 be thoroughly soldered. 



16. Joints should be held together mechanically as well as connected 

 electrically, and should be protected from the action of the air, especially 

 in cities. 



17. Protection.— Copper rods to the height of 10 feet above the 

 ground should be protected from injury and theft by being inclosed 

 in an iron pipe reaching some distance into the ground. 



18. This regulation stands. 



19. Painting. — Iron rods, whether galvanized or not, should be 

 painted; copper ones may be painted or not according to architectural 

 requirements. 



20. This regulation stands. 



21. Curvature. — The rod should not be bent abruptly round sharp 

 corners. In no case should the length of the rod between two points 

 be more than half as long again as the straight line joining them. 

 Where a string course or other projecting stoneAvork will admit of it, 

 the rod may be carried straight through, instead of around the projec- 

 tion. In such a case the hole should be large enough to allow the con- 

 ductor to pass freely, and to allow for expansion, etc. 



22. The straighter the run the better. Although in some cases it may 

 be necessary to take the rod through the projection, it is better to run 

 outside, keeping it away from the structure by means of holdfasts, as 

 described above. 



23. Extensive masses of metal. — ^As far as practicable it is desired 

 that the conductor be connected to extensive masses of metal, such as 

 hot-water pipes, etc., both internal and external ; but it should be kept 

 away from all soft metal pipes, and from internal gas pipes of every kind. 

 Church bells inside well-protected spires need not be connected. 



24. It is advisable to connect church bells and turret clocks with the 

 conductors. 



25. Earth connections. — It is essential that the lower extremity of 

 the conductor be buried in permanently damp soil; hence proximity t<> 

 rain-water pipes, and to drains, is desirable. It is a very good plan 

 to make the conductor bifurcate close below the surface of the ground, 

 and adopt two of the following methods for securing the escape of the 

 lighting into the earth. A strip of copper tape may be led from the 

 bottom of the rod to the nearest gas or water main — not merely to 

 a lead pipe — and be soldered to it; or a tape may be soldered to a sheet 

 of copper 3 feet by 3 feet and 1-16 inch thick, buried in permanently 

 wet earth, and surrounded by cinders or coke; or many yards of the 

 tape may be laid in a trench filled with coke, taking care that the 

 surfaces of copper are, as in the previous cases, not less than 18 square 

 feet. Where iron is used for the rod, a galvanized iron plate of similar 

 dimensions should be employed. 



26. The use of cinders or coke appears to be questionable owing to 

 the chemical or electrolytic effect on copper or iron. Charcoal or pulver- 

 ized carbon (such as ends of arc-light rods) is better. A tubular earth 

 consisting of a perforated steel spike driven tightly into moist ground 

 and lengthened up to the surface, the conductor reaching to the bottom 

 and being packed with granulated charcoal, gives as much effective 

 area as a plate of larger surface, and can easily be kept moist by con- 



