QUARRY AND QUARRYING 



ease within its borders. General government 

 regulations provide for protection of a country 

 as a whole; each smaller political division, 

 down to the municipality, may and does take 

 steps to defend itself individually against infec- 

 tious diseases. The power vested in the au- 

 thorities for quarantine purposes is practically, 

 and within reason, unlimited, even overriding, 

 when considered necessary, personal property 

 rights. No recovery can be made from state or 

 municipality for destruction of property or 

 premises when quarantined and destroyed by 

 order of the duly-appointed health official, but 

 if that official wilfully exceed his duty or pow- 

 ers he may be held personally liable. 



Consult Baker's Laws Relating to Quarantine; 

 Parker and Worthlngton's Public Health and 

 Safety. 



QUARRY, kwahr'ri, AND QUARRYING. A 

 quarry and a mine differ in but two essentials. 

 The former is an excavation in the earth, open 

 to all observers, from which are taken large 

 masses of rock of peculiar quality, such as mar- 

 ble, granite, limestone, sandstone and other like 

 building stones. A mine, while it is an exca- 

 vation, is not visible from the surface of the 

 earth ; the excavation is often over half a mile 

 below the surface and is reached by shafts sunk 

 to the various levels, where workmen seek 

 metals and minerals. Such is the legal aspect 

 of the two terms. 



The operations by which valuable rocks in 

 huge masses are taken from their natural loca- 

 tions and prepared for commercial purposes are 

 known as quarrying. There are two processes 

 which are employed in a quarry. One is known 

 as the "plug and feather" method; the other, 

 the explosive method. 



Plug and Feather Method. Pressure, con- 

 stantly increased and exerted uniformly, will 

 split a mass of rock along a line of cleavage. 

 By employing such means workmen can break 

 rock into such masses and into such shapes as 

 suit their needs; the use of explosives, on the 

 contrary, while sure to detach large masses, 

 may destroy much valuable stone by breaking 

 it into pieces too small for their intended use. 



; nncipal tools in the plug and feather 



hod arc a wedge, or plug, flat on its two 



opposite surfaces, and two "feathers," each 



rounded on one side and flat on the other. 



the rock in a straight line at short in- 



iioles about three-fourths of an inch 



in . .: drilled. A plug is placed be- 



n two feathers and these three pieces arc 



inserted in a hole. When all the holes along 



QUARRY AND QUARRYING 



the line where the rock is to be broken are 

 thus filled, the workmen begin to drive the 

 plugs and feathers downward. Each of the 

 wedges thus formed is driven only a little way 

 at a time, and thus the pressure is kept practi- 

 cally uniform ; eventually it is so great that the 

 rock breaks. 



The mass thus released is turned over to 

 other workmen, who may in turn subject it 

 further to the plug and feather process, or they 

 may break it into smaller pieces by such hand 

 tools as drills, picks, hammers and wedges. 

 Still another class of artisans, more skilled and 

 possessed of the artistic sense, work the smaller 

 pieces into merchantable forms. When large 

 pillars, columns and the like are prepared, ma- 

 chinery is employed in rounding and polishing 

 them. 



Explosive Method. Usually this is employed 

 in detaching great masses of rock from their 

 beds, and for this process either dynamite or 

 gunpowder, connected at a safe distance with a 

 slow-burning fuse, is commonly used, the choice 

 depending upon the results sought from the 

 explosion. If finely-broken pieces of stone are 

 desired, and these are to be further crushed for 

 road making, for manufacturing concrete, and 

 the like, dynamite acts powerfully. When 

 stones of as large size as possible are sought, 

 the milder explosive is employed. In either 

 instance drill holes are sunk deep into the solid 

 mass of rock parallel to the exposed perpen- 

 dicular face of the mass; into these the ex- 

 plosive is then poured and electric wires are 

 connected with each charge. The explosions 

 resulting when the charges are fired are thus 

 simultaneous, and sometimes hundreds of tons 

 are thus forced out in a few very large pieces. 



Extent of the Industry. Of granite, lime- 

 stone, marble and sandstone quarries in the 

 United States there were in 1916 a total of 

 3,067 enterprises, each in number as follows : 



Granite 710 Marble 88 



Limestone 1674 Sandston . 695 



The principal producing states in each com- 

 modity, with the number of quarries credited 

 to each, were as follows: 



Granite. Those states possessing over thirty 

 quarries are California, 62 ; Connecticut, 88 ; 

 Georgia, 32; Louisiana, 85 ; Massachusetts, 82; 

 Minnesota, 36 ; New Hampshire, 40; North Caro- 

 lina, 32; Pennsylvania. 43; Vermon 



utonc. The states with over thirty quar- 

 ries producing; this popular building stone are 

 Illinois. 81 ; Indiana, 126 ; Iowa, 90 : Kansas. 102 : 



S3 : Minnesota, 90; Missouri. 144 

 York, 127; Ohio, 144; Pennsylvania. 311; Ten- 

 -; Wisconsin, 110. 



