14 



Indiana University Studies 



hand process would formerly cut from 5 to 10 feet; that is, a groove 1 foot 

 deep and from o to 10 feet long per day. For this he would receive 25 or 

 30 cents per foot. 



Little use is made of channeling machinen^ in foreign countries 

 where most of the deep cutting is done b}^ means of the pene- 

 trating pulley. This is a type of wire saw which is guided in its 

 course thru the rock b}^ means of a pulley which penetrates the 

 rock bed. 



The channeling machine in use today is simply a combina- 

 tion of drill bits carried in sets and acting from a single cylinder. 

 The motive power might be steam, compressed air, or electricity. 

 All three kinds are in use in the Oolitic limestone district. The 

 electric channeler seems to be doing the best work or at least 

 the most economical work. The consumption of power is less 

 and the cost of producing it in a central plant is far lower than in 

 the channelers carrying their own boilers. The compressed air 

 type of channeler is probably the least economical, on account of 

 the heav}^ line losses and the heav}^ first cost of installing the 

 compressor machinery. 



There are three principal types of channeler in use in this 

 district: the Wardwell, the Sullivan, and the Ingersoll-Sargent. 

 They differ chiefly in the method by which the power is applied 

 to the drill bits. The direct-acting types are the most rapid 

 cutters, but there is a question as to whether the added power 

 consumption does not offset the gain in speed of cutting. The 

 development of channeling machiner}^ has been rapid, and the 

 modern types will cut rock channels at a high rate of speed. 

 Tests on an Ingersoll-Sargent machine have shown as much as 

 100 square feet of channel cut per hour and over 700 square feet 

 of cut in a 10-hour day of work. 



The successful channeling machine, in addition to being a 

 rapid cutter, must have great endurance and reliability inas- 

 much as the constant jar to which the machine is subject will 

 soon destro}' a weak machine. Three motions are essential in a 

 channeling machine: cutting, feed, and motion along the track. 

 In some types of channelers these motions are controlled by three 

 different engines; in others, cog-wheels and shafts make it possible 

 to handle more than one motion with a single engine. The best 

 results have been obtained in the machine with three engines. 



After the channels have been run and the key block has 

 been removed, the blocks of stone are cut loose by means of 

 plugging with drills, and by feathering. When the block begins 



