198 TOWERS AND TANA'S FOR WATER-WORKS. 



ter, a galvanized and ornamental cornice may be introduced, 

 riveted to the eaves-angle and tank-plate or as shown in Fig. 52. 



For tanks of larger capacities, rafters consisting of steel angles 

 or channels may be specified, spaced to carry a light steel roof, 

 or provided with purlins upon which is laid a wooden roof covered 

 with galvanized steel plate. Such construction permits gables and 

 ether architectural features. In the design of the Jacksonville, 

 Fla., water-tower, the cone-shaped roof was surmounted by four 

 gables, and its apex was adorned by an elaborate finial, and in 

 which was introduced an electric-light globe. 



With curved rafters a pagoda- shaped roof is formed. This 

 design, while ornamental in detail, is probably no more desirable 

 than the conical roof either in construction or actual appearance. 



For ornamentation as well as to stiffen the roof construction, 

 a wooden or gas-pipe flagstaff, commencing at the top of the tank 

 proper, secured by radial ties to its shell and projecting through 

 a bent steel collar plate at the roof apex, is sometimes added, 

 otherwise for tanks of large diameters a vertical rod and radial 

 ties similar to those shown in Fig. 52 should be required. 



Trolley- rail. Some i8to 24 inches below the circumscribing 

 angle or plate at the top as suitable shape, as a Z bar, should 

 be riveted to the shell to form a rail for a painter's trolley or trav- 

 eller, and which serves the dual purpose as a convenience and 

 a stiffener to the top of the tank. 



Ladder. If the posts are latticed, the lacing may be used 

 to reach the girder at the top, otherwise along one of the legs, 

 commencing about ten feet from the ground, a light ladder, con- 

 sisting of, say, two 2"X| bars, connected by f" horizontal rungs, 

 spaced 18 to 24 inches should be fastened at intervals of about 

 10 to 12 feet with steel clips to the post and leading to a 2o-inch 

 opening in the balcony floor, extending along the tank shell and 

 terminating at its top. When roofed, a trap opening of about 

 20 inches and an opening in the roof overhang should be pro- 

 vided. As there is an element of danger in the opening in the 



