232 Mr. N, S. Maskelyne, [March 23, 



there were H dirham pieces (corresponding in their ratios to the 

 modern ones of Bussorah), whose weight is about 75 grains. The 

 Ghaznavid coins of the 1st Pathdn sovereign of India, Muaz-ud-din, 

 A.D., 1193, tally with these ; one of them, indeed, is inscribed as a 

 dirham, and weighs 74 grains. The base of the modern ponderary 

 system of Bokhara is stated by the Parsee writer, Nowrozjee Fur- 

 doonjee, to be a mishkal of 71 grains, so that the limits of range of 

 the mishkal of Bokhara and Ghazni, were probably from 74 or 75 

 grains in the 10th and 11th century, to 71 in modern times, and in 

 the days of Baber, as rendered probable from his coins, the margins of 

 which are much worn, it was probably not less than 74 grains — which 

 indeed is still the weight of the goldsmith's mishkal, in Persia — 

 and corresponds to the relation recorded by Makrizi and Abu'l fuzl, 

 as subsisting between the Syrian or Indian mishkal and the Greek 

 dinar (the 66-grain coin of the caliphate). A mishkal of 73*69, 

 would give the weight of the Koh-i-Nur ; and is in fact, even at the 

 present day, almost precisely the Arabian gold miscal of 73 * 368 grains 

 troy. Another resource for the determination of this point, is to be 

 found in the Indian weights, for which the Emperor Baber gives the 

 Persian equivalent, in a remarkable passage in his memoirs, that has 

 been apparently overlooked by numismatic writers. 



The ratios he gives, are 4 Mashes (of 8 ratis)=l Tank, 



5 „ =1 Mishkal, 



12 „ =1 Tola, 



and he adds, they weigh jewels and precious stones by the tank. Until 

 the time of Shir Shah, the tola, as determined from the Pathan coins, 

 was a weight of a minimum value of 174, and probably as high as 176 

 or 177 grains. In Baber's time, therefore, it may be taken at this 

 value. The tank also, as deduced from the a'dhali of Mohammed 

 ben Tughlak, would accord with this estimate. 



Abu'l fuzl states the a'dhali to have been half a dam, and the dam 

 to have been five tanks. Mohammad-ben-Tuglak's a'dhali weighs 

 140 grains. These must be assumed to have been issued, or to have 

 been estimated at a mint value of 1 46 grains, to give the tank of 59, 

 and a tola of 177 grains, an assumption by no means too great for coins 

 of that sovereign. The rati, the little red and black seed of the Abrus 

 precatorius, is far too uncertain and variable a weight to be made the 

 basis of a calculation of the kind. 



The 320 ratis of Baber, and the 319^ ratis of Tavernier, would 

 give an error of some ten carats for every tenth of a grain error that 

 might be made in the estimate of the value of the rati, as the unit in 

 such a calculation. 



There are two kinds of rati-weight ; the goldsmith's of 8, and the 

 jeweller's of 6 ratis, to the same masha. There is also a pearl rati. 

 The only possible means of assigning a value to these weights is by 

 arriving at some result with regard to the tank, the tola, the masha, or 

 the mishkal, and deducing the value of the rati from these. Tavernier 

 has obviously fallen into an error regarding the relative value of this 



