Daily Arizona silver belt., 1908-08-12
PROSPECTING WITH
 CHURN DRILLS
AS PRACTICED IN JOPLIN, Mo, DISTRICT ITS ADVANTAGES AND ECoNoMY-sMALL OUTLAY OF MONEY IS REQUIRED.

| Considerable interest has been
 aroused locally by the announcement
 that ehurn drills are to be used to pros
 pect the Keystone property, adjacent
 to the Miami Copper company s mine
 This method of exploring mineral
 ground at depth is unknown in this dis
 trict, although churn drills are now be
 ing used to prospect the sulphide de
 posits at Ray in the Kelvin district
 Arizona. IL is common practice, and very successfully employed in the Joplin zine and lead field.
 In Mines and Minerals for August, Otto Ruhl writes interestingly of pros pect drilling in the Joplin district.
 "The knowledge desired in all prac- tical prospecting consists of not only To. eating the ore body, but in the de termination of its depth, its vertical and horizontal extent, the character of the ore and associate gangue, and the kind of ground in which the ore body lies. In the Joplin district this knowl- edge has, up to the last decade, been obtained in haphazard and expensive manner The early prospector observed the Clay of the ground'' and the loca- ton of his lease with respect to known deposits, if there were any, and then sunk shaft. Many of the older camps are honeycombed with these prospect shafts. This method of prospecting, while reliable, is too expensive and slow and finally yielded to the more modern practice of drilling. The drilling in this field is done with churn drills ex. clusively, the ehangeable character of the ground being unsuited to the use of diamond drills.
 "Any churn drill which is substan- tial and has good traction may be used. Good tractive power is essential on ac count of the requency of removal The uniform good roads throughout the dis trict make long hauls easy, but in the prospecting of large tracts the hauls are often across soft ground. Drills of the Keystone and Star type are uni formly employed with success. These machines should weigh not less than $500 pounds and preferably from l2,- 900 pounds to 14,000 pounds. Bits should always be in duplicate in order to save time in sharpening, one being sharpened while the other is used There should also be two sizes of bits, the common sizes being 59s and 79s inches. In addition there should be full set of finishing tools. A black smithing outfit consisting of blower, hammer, sizing device, anvil and billet, and tub for tempering is indispensable The anvil need be only heavy piece of wood with a steel bar at one end to support the drill bit while at the other end depression in the wood is made or a heavy piece of oak is bolted on to hold the bit in place during the ham, mering. Wrenches, driving hammers, and pipe-pulling devices are also part of the necessary equipment. The sand bucket to hoist the drill cuttings may be of the vacuum-pump pattern or merely the ordinary steel bucket with clack valve at the bottom, the latter being the most common in this field. 
 ''The difficulties which drillers meet in this district are greatly minimized where holes are carefully cased the entire depth The great trouble comes
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