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This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.Scholars believe, and we concur, that this work is important enough...

This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it.This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.Scholars believe, and we concur, that this work is important enough...

Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve ...

Excerpt from Lead OresLead, although one of the commoner of the base metals, is present in the earth's crust only to the extent of a fraction of I per cent. Of the whole. In workable deposits, however, the proportion is much higher owing to a natural concentration of material. Lead is closely associated in nature with zinc, and their primary or sulphide ores commonly occur together. Zinc ores are more soluble than lead ores, hence in the zone ...

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Excerpt from Lead Ores The Imperial Institute is a centre for the exhibition and investigation of minerals with a view to their commercial development, and for the supply of information respecting the sources, composition and value of minerals of all kinds. The Imperial Institute is provided with Research Laboratories for the investigation, analysis and assay of minerals, and undertakes reports on the composition and value of minerals for th...

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