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( 557' )
The Cologne ounce is “ 8x92 ftandard pts. and the Troy ounce is ~ 8724 ft. pts. whenc®-.the Cologne ounce, and eighth of an ounce (or quentchen) is = .939018 1 roy ounce or dram-refpe&ively : and the Cologne mark is'= 7.51 2144 Troy ounces : or by the following table ;
When gold and fdver are weighed in Germany by the Cologne mark, it has a totally differentfubdiviGon from the common ounce, quentchen, and pfenning.
For gold, the mark is divided into 24 carats, and the carats into 12 grains. The Carat there-fore, where it is a real weight, is equal to 150.242 Troy grains, and the Grain, or 288th partof the mark is equal to 12.52 Troy grains.
For filver, the mark is divided, as ufual, into 16 Loths, or half ounces, but the loth into 18Grains. The grain is in this cafe alfo the 288th part of the mark. This circumftance ofemploying the term grain occafionally for a fubdivifion of the mark, and giving to it a valueupwards of 13 times the Nuremburg grain fhould be carefully noted, as many errors may arifefrom it, particularly to the Englifh reader.
The method of conducing the affay of gold and fdver has been deferibed under the articleAssay, and it is there mentioned (p. 117) that the fmall piece of gold cut off the ingot to beaffayed is called an Affay mark, and (like the real mark of gold) is divided into 24 carats, andeach carat into 12 grains, by fmall fets of weights ufed for this purpofe. I he aftual quantityof gold ufed for this purpofe is half a pfenning, or -5T2 of a real mark rz 128 ftandard parts,or about 7 grains Troy. The affay grain is further divided into halves and quarters. TheAJfay mark for Silver is divided as the real mark for this metal, namely, into 16 loths, and eachloth into 18 grains, and the grain into halves and quarters; and the real weight of the filverallay mark is twice that of gold, or one pfenning.
The German affayers and mineralogifts have alfo the Docimejlic Centner, which has generallythe a£tual weight of one qUentchcn (equal to. 56.34 grains Troy) but is fubdivided into 100docimaftic pounds, each of which therefore is equivalent to about -§ grain Troy.
The moft common meafure of length in Germany is the Rhinland foot, to which ftandard thefoot, ell, &c of the different ftates is ufually compared.
With regard to the length of this meafure in Englifh inches, the Pied du Rhin is faid inPeuchet’s Diet, de Commerce, to be — 11 inch. : 7 fines, of the old French pied de rot, whichis 12.241 Englifh inches. Hence we have the following •numbers, viz. x Rhinland foot= 12.34c Englifh inches, and therefore 1 Rhinland inch = 1.02''42 Englifh inches, and 1cubic inch Rhinland = 1x8769 Englifh cubic inches, = 274.64b Troy grains of diftilledwater = 286.31. Nuremb. grains.
On the other hand, Klaproth in his analyfis of the Cartftxid water, and in the other parts ofhis works, employs the cubic inch, which, he fays, holds 2Qo of the true Nuremburg grainsof diftilled water, and which appears to be as common a ftandard of length among the German chemifts as the Nuremburg is of weight. Now according to Gren, 290 Nuremb. grains, =2‘8.i875Troy grains, rr 1.10169 Englilh cubic inch, of water, and the cube root of i.ioiyoo-}-(which hardly differs from 1.101693) is 1.032812. So that the inch ufed by Klaproth is probably the Rhinland inch, which by this eftimation is = 1.032812 Englifh inches, andby the former is rr 1.02842, Englifh inches, the difference being only about .0044.