Table 4. 



21 



Table 5 contains the values of T„ aud T,,,. These are fuUy corrected, 

 not only for the division errors of the scale, as formerly determined by Gill, 

 but also for the différence between the total leugth of the scale, and the total 

 length of the reseau line 14 or 43 with which it was compared. In this cor- 

 rection allowauce was made for the effects of sinuosity and projection error, 

 so that the standard is the corrected line, and not the actual reseau line. 



