. Engineering and Contracting. thewalls of the tower, the latter ring beingriveted to the lower course of the tank. The course, that the radii of the segments formingthe successive ribs decreased with the heightof the rib. Tapered lagging was used, beingmade by double dressing 2x6-in. pieces to l%x513/16 ins. and ripping on a diagonal, thusmaking two staves, 3 ins. wide at one end and2% ins. wide at the other. This tapered lag-ging was used again on the 4-ft. belt andcornice forms, the taper being tunned alter-nately up and down. The interior diameter being uniform upto the bottom of the dome,
. Engineering and Contracting. thewalls of the tower, the latter ring beingriveted to the lower course of the tank. The course, that the radii of the segments formingthe successive ribs decreased with the heightof the rib. Tapered lagging was used, beingmade by double dressing 2x6-in. pieces to l%x513/16 ins. and ripping on a diagonal, thusmaking two staves, 3 ins. wide at one end and2% ins. wide at the other. This tapered lag-ging was used again on the 4-ft. belt andcornice forms, the taper being tunned alter-nately up and down. The interior diameter being uniform upto the bottom of the dome, collapsible formswere used from the beginning. These foririswere constructed in six large sections, 6 , with one small key section with wedgepiece to facilitate stripping, as shown in There were three tiers of these, bolted;end to end horizontally and to each othervertically. Above the taper base and except in the and cornice, collapsible forms were usedon the outside also. There were sections i I. INSIDE FORM Fig. 1—Movable Forms for Shaft of Concrete Water Tower. tank is covered with a roof of reinforcedconcrete, 4 ins. thick, conical in shape, andreinforced with %-in, twisted steel bars. The tower is built on out-cropping, solidrock. This rock was roughly stepped, anda concrete sub-base built. This sub-base con-sists of a hollow ring, with an inside diameterof 20 ft., the walls being 5 ft. thick. It is about2 ft. high on one side and 7 ft. high on theother, and forms a level base on which thetower is built. The forms for this sub-baseconsisted of vertical lagging and circumferen-tial ribs. The lagging is of double-dressed,2x3-in. segments, and the ribs are of 2xr2-in. segments, 6 ft. long, lapping past oneanother and securely spiked together to formcomplete or partial circles. These ribs arespaced 2 ft. center to center. Similar construction was used to form thetaper base of the tower proper, except, of •Abstracted and rearranged from a pape
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