STAMPS AND PULVERISERS.

Otago Witness, Issue 1323, 7 April 1877, Page 4

STAMPS AND PULVERISERS.

If of anything, the " Great West" may boast of multiplicity, and variety- of stamps ; but with all that it, remains a fact that stamps constitute the , least economical and the least rational, as,well as the most clumsy and the most aw,kwardy contrivance -.for - ore breaking., . , r What crusher and roller can ,do, ,- therefore, should never be attempted- by stamps. Among all the different patterns in. use of late, the introduction of stamps deprived of the feature of cams have been tried. 1 They differ only in. the motion, , but not in the effect of , the blow, from older; ,pat- : terns. The so-called, ateam stamps have a sfceel cylinder and.pitman t6 each, head. The "atmospheric stamps" moye by. a 1 curved shaft, and have, air, cylinders W temper the blow. '„. , : „,, ,; .. \ Hqwland's rotary pulverising.and amal-, gamatiug quartz mill ,wiil tj .be* found to answer all purposes best where stamp', mills will bo needed, for a, reserve action^ Ln mineral dressing, and possesses many: advantages which others do not, of which \ not the least is that % its work is jreduced^ to a rotary-motion in a,high.er degree than with any other kinipf. stamp mill. : -, ■ Pulverisera, .whether on the ball or 'burr ] principle, do not do the 'kind of work re.quire.d for concentration, because 1 they! equalise, the ahape, of .^particles top, much. | and "deatroy a quality (cieavage),,which' ■has lo assist in concentrating sizes of very ! small dimensions. *, . ■ . . .; • ' Unless the ore M when brought; to .the crusher, beat least dry enough, jvith^the assistance of the dust , produced by ;the pruahing itself, not. to clog, it w©uld ,be advisable to add .water!; but if the ore is not clayish, or of a clogging nature, .dry crushing is preferable/ ,and thp same ia the case for rollers.,, AH,, the, sizing which phouldvbe done t betweenj ,cruaher and rollers, so as to withdraw from further action what doea not. require, it, and.alab all aiding, "sq as, to, ; retain what requires further, breaking,, can -be done dry;, L and .is/ indeed "done, diyj,with better, adya^tage^^r^t^ijiZfcT. :F.\ Cftzii^ M.jS.^'Santa^.e, [N^w Mexico. \ , h ,'. :fl P!i