THE POLK SYSTEM MACHINE 



hoisted by means of a rope and series of pulleys so arranged 

 that the hoisting force is applied horizontally from with- 

 out the structure. A small opening thru which the hoist- 

 ing rope works is cut in the wall near the bottom of the 

 first fill of concrete. When the bucket has been hoisted 

 it is coupled to the carrier on the crane by means of a 

 hinged hook. Then it is swung to any part of the wall 

 space desired. 



The scaffolding, both inner and outer, is swung from 

 the steel Tees which project some distance beyond the 

 wall. 



fl . . The operation of the machine is very simple. 

 UperatlOn 



forms are set, the reenforcing bars are 

 placed in position, the concrete is mixed, hoisted, dumped 

 and packed between the forms, and allowed to set. 



On the next morning the nuts connecting the sections of 

 the outer forms are loosened, the steel wedges fixing the 

 sections of the inner forms are lifted, and both inner and 

 outer forms swing free from the wall. Then by means of 

 the jacks resting on the widely flanged base collar, the 

 whole mechanism is lifted until in position for a new 

 fill and the forms again are set by means of the bolts and 

 the wedges. 



The actual raising of the forms for a new fill does not 

 require more than ten minutes. Though some POLK 

 SYSTEM contractors have successfully placed two fills a 

 day during hot, dry weather, one fill >a day is the most 

 satisfactory rate of progress. 



Arlvnnf arr The POLK SYSTEM machine automatically 

 Advantage* keeps the wall of regular thickness, true to 

 a circle and perfectly plumb. It does away with an 

 always risky system of scaffolding and allows no strain 

 on the "green wall." It is especially adapted for high 

 work. It also provides a rapid and economical means of 

 hoisting and depositing concrete in the form. Besides all 

 of this the contractor can, with the standard POLK 

 SYSTEM machine, build any sort of circular reenforced 

 concrete work, such as grain storage bins, coal pockets, 

 smoke stacks and water tanks, besides the silos that the 

 farmers are calling for. _ 



Everybody Believes in the Polk System 



