Mance: Quarry Industry of Southern Indiana 



63 



electrical equipment has been installed it has been found to be 

 far more economical than the old line shafts and belting with 

 their accompanying losses of power. The electrical equipment 

 in use thruout the district is in good condition and is giving 

 satisfaction. The electric motor seems to be better fitted for 

 derrick handling than smy other form of power unit and its 

 efficiency has also been proved in driving mill machinery. As 

 has already been said, the direct-connected generator is doing 

 better work than the belt-driven generator wherever it has been 

 installed, and its greater efficiency seems to justify the greater 

 ffi-st cost of installation. 



Compressed air is in use in most of the mills for decorative 

 work, and practically all of this equipment has been furnished 

 by the Chicago Pneumatic Tool Company, of Chicago and New 

 York, and the Ingersoll-Rand Compan^^ of New York. The 

 use of compressed air in this line of work has been an important 

 factor in the decrease of the amount of skilled labor employed in 

 the stone-cutting business. One laborer working with compressed- 

 air tools can do as much carving as five men working under the 

 old system. Where compressed air is used in the operations of 

 channeling and drilling, the machinery employed is on a much 

 larger scale, and the equipment is usually of types furnished by 

 the Sullivan Machinery Company or the Ingersoll-Rand Com- 

 pany. There are two companies using compressed air for channel- 

 ing purposes in the district at the present time, but in both cases 

 it has been found to be an uneconomical procedure. This sub- 

 ject will be further discussed in another part of this study under 

 the head Power and Machinery. 



The Ideal Quarry Power Plant. The quarry owner will 

 always be found ready to talk of the quality of the stone and of 

 the methods of its production, distribution, and use, but when the 

 quarry power plant is mentioned his information fails. Few of 

 the men who are bearing the expense of power-plant operation 

 can tell where the money spent for coal goes, and even if they 

 have tried to determine it, few have been able by such study as 

 th,e\' could give to the problem to check the unnecessary drain 

 from this source. Mr. D. ^l. Myers in his paper on "The 

 Mechanical Engineer and the Factory Power Plant" says: 



As regards his po^ver plant equipment, the operator must strictly speeifj^ 

 and obtain thi'ee things if he is to have the ideal power plant. These are as 

 follows: (1) Xo shut-downs or delays, or at least as ^e^\ as possible. (2) 

 An efficient power equipment Avith minimum bills for fuel, labor, main- 



