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A Dictionary of Arts: Island Moss.


A Dictionary of Arts, Manufactures, and Mines; containing A Clear Exposition of Their Principles and Practice

by Andrew Ure, M. D.;
F. R. S. M. G. S. Lond.: M. Acad. M. S. Philad.; S. PH. DOC. N. GERM. Ranow.; Mulh. Etc. Etc.

Illustrated with nearly fifteen hundred engravings on wood
Eleventh American, From The Last London Edition.
To which is appended, a Supplement of Recent Improvements to The Present Time.

New York: D Appleton & company, 200 Broadway. Philadelphia: George S. Appleton, 148 Chestnut St.
MDCCCXLVII

1847

ISLAND MOSS (Lichen d'Islande, Fr.; Flechte Isl., Germ.) is a lichen, the Cetraria islandica, which contains a substance soluble in hot water, but forming a jelly when it cools, styled lichenine by M. Guerin. Lichenine has a yellowish tint in the dry state, in transparent in thin plates, insipid, inodorous, and difficult to pulverize. Cold water makes it swell, but does not dissolve it. It is precipitated in white flocks by alcohol and ether. Iodine tinges it of a brownish-green. Sulphuric acid converts it into sugar; and the nitric into oxalic acid. Lichenine is prepared by extracting first of all from the plant a bitter colouring matter, by digesting 1 pound of it in 16 pounds of cold water, containing 1 ounce of pearlash; then draining the lichen, edulcorating with cold water, and boilin it in 9 pounds of boiling water till 3 pounds be evaporated. The jelly which forms, upon cooling the filtered solution, is dark colored, but, being dried and redissolved in hot water, it becomes clear and colorless. Lichenine consists of 39.33 carbon, 7.24 hydrogen, and 55.43 oxygen. With potash, lime, oxide of lead, and tincture of galls, the habitudes of lichenine and starch are the same. The mucilage of island moss is preferred in Germany to common paste for dressing the warp of webs in the loom, because it remains soft, from its hygrometric quality. It is also mixed with the pulp for sizing paper in the vat.

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