692 
LORD RAYLEIGH OR THE VALUE OF THE BRITISH 
For F at 17° we take 128*130 (see p. 137 of former paper), so that 
/=63*574. 
Thus 
and 
log (27r/0^)=lO*77832=: log (10 10 X 6*0023), 
1 0 10 v 6-0093 
R= N(tan ft- tan ,ft 0 ) B( 1 + -00422 sec <t>) + \/{i( l + ‘ 0()ii2 sec '/-) 2 -U( tan tan 4) 3 }] 
in which 
log U=‘84325 
Table III.—Second series. 
Humber Of teeth. 
60. 
45. 
35. 
30. 
R by preceding formula in ohms. . 
23-639 
23-655 
23-660 
23-651 
23-670 
23-659 
Resistance of standard at 16° . . . 
23-642 
23-658 
23-663 
23-654 
23-673 
23-662 
Resistance of standard at 13°. . . 
23-621 
23-637 
23-642 
23-633 
23-652 
23-641 
The immediate result of the formula is the resistance in absolute measure of the 
revolving circuit, on the supposition that with the connecting bars it exactly balances 
the standard at 16°. The resistance of the standard itself is therefore given by 
addition of the resistance of the bars, i.e., *003 ohm. In the last line the results 
are reduced to the temperature of 13° for comparison with the third series. 
