Pacific service magazine . ity byadding a marketable quality, thus trading ashipping point for a selling point. The different colors and markings in themarble were caused by the intrusion ofmineral or organic matter at the time ofthe metamorphosis. Graphite, which, by theway, is metamorphic coal, gives the delicategrey tones and markings; iron gives thetans and yellows; copper the greens andblues. Nature with an ever present decora-tive sense traced her colors in marble witha fine brush, while in the Grand Canyon ofthe Colorado, with the same pigments, shelaid them on with a metaphoric fire ho
Pacific service magazine . ity byadding a marketable quality, thus trading ashipping point for a selling point. The different colors and markings in themarble were caused by the intrusion ofmineral or organic matter at the time ofthe metamorphosis. Graphite, which, by theway, is metamorphic coal, gives the delicategrey tones and markings; iron gives thetans and yellows; copper the greens andblues. Nature with an ever present decora-tive sense traced her colors in marble witha fine brush, while in the Grand Canyon ofthe Colorado, with the same pigments, shelaid them on with a metaphoric fire hose. On the 140-acre property of the Colum-bia Marble Company, twenty-one differentvarieties of marble have been found, blue,blue-white, grey, grey-white, black, varie-gated combinations of all of them, and end-ing up with a pure white statuary marblethat is the equal of any statuary marble inthe world. Quarrying.—Marble is quarried out inbenches. For the purpose of illustration,picture your front steps as marble and mag-. The Columbia Marble Companys quarry near Sonora. This view shows the bench method ofquarrying. The 1200-foot cable lift to the mill is shown in the right-hand corner. 214 Pacific Service Magazine nified about sixteen times. In or-der to quarry them in the orthodoxmanner, we start with the top step,about three feet in from the edgeand drill holes with a pneumaticdrill about an inch apart and paral-lel with the edge of the step. Thenwe drill holes horizontally on thelevel of the next step to meet thebottoms of the vertical drills. Theblock thus formed is broken outalong the line of the holes withwedges—dynamite would eithershatter the ledge or crack the the next step the same proced-ure is followed, and so on until theentire mass is quarried out. In the actualquarrying operation the problem is intensi-fied because the benches must be cut awayfrom the retaining side walls. Pacific Ser-vice answers the question by driving a 12-horsepower motor on the
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Keywords: ., bookcentury1900, bookdecade1910, bookidpacificservi, bookyear1912
