The elements of conchology; or, natural history of shells. According to the Linnean system. With observations on modern arrangements / By Thomas Brown ... Illustrated with nine coloured engravings.

  • Thomas Brown
Date:
1816
Catalogue details

Licence: Public Domain Mark

Credit: The elements of conchology; or, natural history of shells. According to the Linnean system. With observations on modern arrangements / By Thomas Brown ... Illustrated with nine coloured engravings. Source: Wellcome Collection.

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    of the sun, or as the index or hand of * a clock moves. “ But in order to be more clearly understood, let us compare the spiral volutions of a shell to a common cork- screw, and we shall find that v/hether the mouth, or apex, is placed up- wards, the spires will turn from the upper to the lower end like a common screw, which is in the same direction as the index of a timepiece, and what is commonly understood by a dextral or right-handed screw. As a fur- ther definition, such shells have their aperture on the right side, when examined with that end downward; and is in the direction of the sun^s apparent motion.^ * That different authors have described both sides of the shell as the right, is very clear; but it appears to me, Mr. Mon- tagu has himself run into a mistake, concerning tlie right and left sides of the shell; and I have termed that side of the shell with the aperture in it, when viewed in front, the side; contrary to Mr. Montagu. It is admitted by most Concholo- gists, that the apex or tip of the spire, is the top of the shell, and the lower region, in which the aperture is situate, is the
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