Analysis of Resins, Balsams and Gum-Resins; The Chemistry and Pharmacognosis. for the Use of the Scientific and Technical Research Chemist. with a Bibliography

Analysis of Resins, Balsams and Gum-Resins; The Chemistry and Pharmacognosis. for the Use of the Scientific and Technical Research Chemist. with a Bibliography

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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1901 edition. Excerpt: ...was also referred to by earlier authorities, such as Mylius, Gehe & Co., and others---seems still to be the case, and, apparently, perfectly pure commercial storax is practically non-existent. Evers says--The various kinds and forms of storax will now be dealt with in detail seriatim. I. Crude Storax (Styrax liquidus crudus).--The numerous examinations made for acid, ester, saponification, and iodine values, and the results obtained, are of merely relative worth in the valuation of storax, because for the most part the determinations were made with alcoholic extracts, and not with the natural storax. The disadvantages of using only portions of a drug, instead of the crude product, have already been fully dealt with in these pages, and therefore need only be mentioned here. It is not clear from the reports of Kremel, Beckurts and Briiche what methods these authors employed, and we must therefore leave it an open question whether they worked with an extract, the crude product, or some other form. At all events, E. Dieterich, Evers, and others used extracts. The present author has recently worked out a method which is suitable for direct application to crude storax, and therefore enables reliable conclusions to be formed with regard to the natural drug. Just as attention was directed by Gehe & Co., Mylius, and others to the existence of adulteration, so various proposals have been made for detecting the same. Thus, E. Dieterich proposed to employ the acid value (direct) for this purpose, seeing that turpentine (ordinary, not Venice, turpentine) and colophony give higher acid values than storax. Similarly, Beckurts and Briiche advocated the ether, saponification, and iodine values for detecting adulteration; and Evers believed that the iodine...show more

Product details

  • Paperback | 118 pages
  • 189 x 246 x 6mm | 227g
  • Rarebooksclub.com
  • Miami Fl, United States
  • English
  • black & white illustrations
  • 1236590880
  • 9781236590886