DECIMAL COINAGE. 251 



Lord Overstone had wisely left Vaughan's Sun and 1856. 

 Moon out of his question. The answer goes on : Jtont'? 



questions 



Vaughan was a clever attorney, who had read more out of 

 law than h"e was able to digest. Sir William Petty will be 

 allowed to have a much better judgment by all who have read 

 in both. In his Quantulum-cunque, reprinted in 1856 by the 

 Political Economy Club, it has been pointed out to me that he 

 speaks as follows : 



' The use of farthings is but to make up payments in silver * 

 (N.B. Copper farthings and silver pence were then in circula- 

 tion), 'and to adjust accompts, to which end of adjusting accompts 

 let me add that if your old defective farthings were cryed down 

 to five a penny you might keep all accompts in a way of decimal 

 arithmetic which hath been long desired for the ease and 

 certainty of accompts.' 



Decimals were not well understood in Petty's time. His 

 system would give 1,200 farthings to the pound. But his main 

 point evidently was that the multiplier 5, by its relation to 10, 

 is an easier multiplier than 4. 



Mr. Vaughan lived at a time when decimal fractions were 

 not familiar to the mass of arithmeticians. It would be easy to 

 show that, up to the year 1700 at least, the mastery over decimal 

 fractions which is common in our day was almost confined to 

 high mathematicians. Mr. Yaughan's statement merely amounts 

 to this, that 12 is better than 10, because it has more divisors. 

 The answer is that 10 is better than 12 because it is the radix 

 of our present system of counting. Mr. Vaughan's objections 

 would be exceedingly valuable if a new system of numeration 

 were to be under contemplation. 



Napoleon at St. Helena is no authority. He had never been 

 a shopkeeper or a money calculator; and if he had been, his 

 position at St. Helena was not favourable to sense or candour. 

 He was grumbling at all creation ; nobody knew his own 

 business, not even the General who commanded against him at 

 Waterloo. He is very unfortunate in his expression. He 

 adopts the erroneous supposition that the decimal system is only 

 useful to scientific calculators, and styles them astronomes et cal- 

 cidateurs. Now the Astronomer is the only scientific calculator 

 to whom, as such, decimalisation is impracticable. He is in 

 such continued connection with the records of his science that 

 lie cannot afford to decimalise angular measure. He is a 



