Rackarock.

Te Aroha News, Volume VI, Issue 375, 8 June 1889, Page 2

Rackarock.

An explosive known as Raekaroek is about to be introduced to this district for the fiist time (though well-known and largely used in America and Australia), which the manufacturers claim surpasses in many most important respects all other explosive, and respecting it those who have given it most thorough and exhaustive tiittls speak in the highest praise. The travelling agpnt of the Rackarook Company, Mr I?, A. McArthur, purposes airivins? at Te A rob a from Auckland to-day, and dining the ensuing wetk vcill demonstrate the povveis of liacknrock at the Tui, Waiorongomai, and at any other mines that may be desired by local residents, and afterwards proceed to Kai^ngahake, Waihi, etc., and on to Thames in the interests of the Company. We understand Mr J, M. Ghambeis Ins been appointed resident agent at Auckland for the sale of Rackarock. Any improvements in the way of explosives is a matter of great importance to a mining community, and we are quite sure the experiments about to ! bo carried out in this district will be { watched with close interest. j From a numbar oC flattering testimonials and Press notices we have seen wo give the following btief extracts : — From Sydney Daily Telegraph, March 27th, 1888: — "An interesting trial was made yosteiday at the Vulcan Brickworks, St, Peters, of the new explosive " Rnokarock." Rackaioek differs from blasting powder and dynamite in being non explosive until mixed for use. Besides rerderingit much safer than oidinary explosives, this effects a great paving in transit charges, as the two constituents of which it is composed can be despatched by rail ( r steamer at the same rate as ordinary freight. In addition to this advantage, it is claimed that it is ten times more powerful than blasting powder, and, further, unlike dynamite, it produces no injuiious fumes. To carry out the experiments yesterda}', holes had been drilled 10 feet deep and 9 feet b'ickf row the face in slate or hard shale. One of these was charged with only 51b of Rackarock and fired, with the result that about 3G tons of shale were blown out ready for uso. In another hole, placed 12 feet back, the vosults were similar, but it will take souie days to estimate npcuyatejy the quantity of shale shifted. In an experimental shot at the Warren brickyard, whero the hole wa-f drilled' only 6 feet from the face, the whole block was blow n out, and ' the material shifted was so completely broken up as to effect in this particular a 'consideiable laving. Th« new explo-iivo is already becoming \ opular among mining men."

I From Gympie Times, July 2, 1888 .' — "Air B. 11. Bonnefts, Manager of No. 2 and 3 South Smithfield G,M. Co., Gympie, sent in the following report to hi.s" Directors, June, 1888 :— "I a:n very pleased to report tho 8! t'afactory lesu't of the new explosive known as Rackamokaftera trial of fifteen weeks, during which time we have used twelve cases, equal in weight to 25 cases oO dynnrnite (the 25 cases of dynamite would only have lasted us nine weeks), and since then I have taken four men out of the faces, which I could not have done if dynnmite had beet in use. I have given the explosive a fair trial, having charged fifty holes myself, and I never saw belter results from any other explosive, I have seen some of the holes woiked 3 feet beyond the bottom oi: the hole; and a miner named Malcolm, working in the mine, tried a hole on Thursday, which worked 6 ftot beyond its bottom. The beauty of the explosive is that there are no ill effects from the fumes. On the 26th instant there was a speci.il t*st of tho explosive, when 22 holes were fired in the pre^enco of Me&sis W. Fiyir (lnspectoi of Mines), R. B. Paikvn (manager Ciown :md Phconix), W. ElfViM.snu (m-ina«ei Wilmot Extended), R. Daddow (manager Hilton Extended), 11. Ball, and nnself ; all the holes were charged, tamped, and woiked well. The trial was given in the crosscut, diive, and slopes." We may mention that our repoiter, in couiso of. conversation with Mr W. Elfverson, elicited that ho is using Kackarock in a crosscut at the 615 foot level in hard and in his opinion the results are quite equal to those of gelatine ; while the fumes are innocuous. Ho says it in nec-PBsnry, ho.ve^e 1 , in order to secure the full effects, that the directions wi'h regard to charging and tamping, which are veiy simple, should be strictly followed." The Charters Towers Daily Ileiald, December 22nd, 1887, also refers in very high terms to this explosive, and in concluding says :—: — " A description of the compound itself will be found of interest. The explosive differs consideiabty from the ordinnry run of, explosives, inasmuch asit consists of two parts — one a fluid, and the other a solid. Neither of. these preparations can bo exploded separately, &o that it can be stored with perfect safety. In order to render the cartridges explosive they have to be dipped in the liquid for five seconds. For this purpose a small wire basket is piovidcd, and as many eartiidges as lequued placed in it and iiumeised in the fluid. The matter of "dipping" is an important opeiation, but yet veiy simple, and m<iy be done by any miner of ordinary intelligence. In this simple matter, as in many others, on'y ord'nnry intelligMiee 13 required to insure complete success. rlher Ihe merits claimed by the fii-m are that it is us powerful as dynamite, never requires to undergo the dangerous process of thawingy,is perfectly safe to handle to transport in its uncombined form, is cheap, and its fumes are hnocunuJu The holes are charged and fired in tbe v 'Rame way as for dynamife and gelatine, .with a detonating cap, and premier sextifple caps are used,"