OF AETS AND SCIENCES. 



S85 



The two values of h for the yard when reduced to the equivalent for 

 one meter become 4.66 div. and 4.57 div. respectively. The meau 

 value of J, therefore, derived from these equations, is 4.49 div. for one 

 meter, or 4.10 div. for one yard. Substituting these values in the 

 equations, we find a few values of a which differ from the mean value 

 more than four times the probable error of a single value. In the 

 formation of the mean values for 0° and for 16°. 67 these quantities 

 have been rejected. 



For the meter, we have 



AtOO 



R^-— G'l'*'^— Sl.ldiv. 



R,^' 



G.f = —28.6 div. 



For the yard, we have 

 Rf _ C,"' = _28.6 div. 

 Bf _ Gf = —29.9 div. 



At 16°. 67 



+42.3 div. 

 +47.7 div. 

 Mean 



+41.9 div. 

 +41.7 div. 

 Mean 



h = +4.40 div. 



b = +4.58 div. 



. +4.49 div. 



h = +4.23 div. 



b= +4.30 div. 



. +4.26 div. 



We have, therefore, finally, 



_ , ^ 7 4.49 div. + 4.65 div. , a "rr j- o ni 



For 1 meter, b = ^^ = +4.o7 div. =: 2.01 /x,. 



„ , , . 4.11 div. + 4.26 div. ' ,iio;i' i q^ 



For 1 yard, 6 = ^ = 4.18 div. = 1.84 /i. 



Since the absolute coefficient for B^ \s 10.11 fi, and 9.24 /x for the 

 meter and yard, the absolute coefficient for the glass bars becomes 

 8.10^ and 7.40^ respectively for the meter and the yard. 



VOL. XVIII. (S. S. X.) 



25 



