ANNUAL ADDRESS OF THE PRESIDENT. XLV 
toise to be of little value because the original toise-¢talon was of 
iron, and the standard temperature in France differed from that in 
England.’ In his opinion the French should have sent over an 
iron half toise in exchange for the English brass yard; but this 
criticism loses much of its force when it is remembered that in 1742 
neither England nor France had fixed upon a temperature at which 
their standards were to be regarded as of the true length. On the 
return of the rod from Paris Mr. Graham caused Jonathan Sisson 
to divide the English yard and the French half toise each into three 
equal parts, after which the rod was deposited in the archives of 
the Royal Society, where it still remains.” Objection having been 
made that the original and legal standard yard of England was 
not the one at the Tower, but the Elizabethian standard at the Ex- 
chequer, the Royal Society requested Mr. Graham to compare his 
newly-made scale with the latter standard, and on Friday, April 
22, 1748, he did so in the presence of a committee of seven mem- 
bers of the Royal Society. In the following week the same gentle- 
men compared the Royal Society’s scale with the standards at 
Guildhall and the Tower, and also with the standard of the Clock- 
makers’ Company. These comparisons having shown that the copy 
of the Tower yard upon the Royal Society’s scale was about 0°0075 
of an inch longer than the standard at the Exchequer, Mr. Graham 
inscribed upon the Royal Society’s scale a copy of the latter stand- 
ard also, marking it with the letters Exch., to distinguish it from 
the former, which was marked E. (English), and from the half toise 
which was marked F. (French).’ 
In the year 1758 the House of Commons appointed a committee 
to inquire into the original standards of weights and measures of 
England; and, under instructions from that committee, the cele- 
brated instrument maker, John Bird, prepared two brass rods, 
respecting which the committee speak as follows in their report: 
“And having those rods, together with that of the Royal Society 
laid in the same place, at the receipt of the Exchequer, all night 
with the standards of length kept there, to prevent the variation 
which the difference of air might make upon them, they the next 
morning compared them all, and, by the means of beam compasses 
brought by Mr. Bird, found them to agree as near as it was possible.” * 
One of these rods was arranged as a matrix for testing end meas- 
134, p.87. 76, pp. 185-8. 97, pp. 541-556. #11, p. 434. 
