132 APPENDIX.
Different
weights and measures appear to have been used in different parts of the
country—the Mangelin = 1-3/4 carats, or 7 grains, at Raolconda and
Colour ; the rati = 7/8 of a carat, or 3-1/2 grains, at Soumelpur.
If
we could with appropriate accuracy fix the value of the rati, or rutti,
mentioned by Tavernier, we might succeed, perhaps, in instituting a
fair comparison between the Great Mogul and other diamonds. It seems to
be difficult to believe that it weighed 3-1/2 grains, as he states. In
Nagpur, in the year 1827, according to Mr. Jenkins, the rati weighed
only 2.014 grains. But it is necessary to bear in mind that the French
grain is only equal to about 77 of a troy grain ; therefore, since the
rati contained 3-1/2 of these, its value would have been 2.605, or say
27 grains troy-This fact seems to have been overlooked by some who have
endeavoured to reduce the weights given by Tavernier. Non-experts,
too, appear to have forgotten that the diamond grain is not identical
with any other grain ; though an English carat contains four of these
grains it only consists of 3.174 troy grains ;* so calculated, the
weight of the Great Mogul would be 319.5 x 2.7/3.174=271.84
English carats. If in this calculation we could feel
justified
in placing the value of Tavernier's rati at 1.84 grains troy instead of
27 grains, the exact weight of the Koh-i-nur would be obtained. Another
system of calculation is used by the writer of a Note in the Great
Exhibition Catalogue of 1851, in which he adopts the known maximum
weight of a rati at 2-5/16 grains (what grains ?), and thence deduces
175 carats as the weight of the Great Mogul. This is somewhat short of
the 186-1/16 carats of the Koh-i-nur, while the other is too large. If
the Koh-i-nur be identical with the Great Mogul, it may have been
operated upon during its travels, and this may account for the
difference in weight (271.78 — 186.06 = 85.72 loss), and in its shape
when brought to England from the sketch given by Tavernier. It is
probable, however, that
* Vide " Encyclopedia Britannica," art. Diamond.
