(Fig. 2) in front of the stand, and laid in the place of the dummy pendulum with ther- 

 mometer. The auxiliary is put in the place of No. 21, and a long arm is firmly attached 

 to its head, carrying a mirror at the end, which lies alongside the mirror of No. 21. 

 The mirror of the auxiliary may be readily adjusted so that the reflections of the scale 

 from the two mirrors appear side by side in the telescope. 



A specimen form in which the observations for flexure are made is put down below. 



Apr. 3rd, 1913, 2.30 p.m. Nos. 21 and Auxiliary. 

 " Driving " pendulum = auxiliary. 

 "Driven" = No. 21. 



Start 7 hr. 35 min. 



Time. 



hr. min. 



7 51 

 5H 

 52 



53 



53i 



54 



55 



55J 

 50 



57 



57 \ 

 58 



59 

 59J 

 8 00 



1 



1J 

 2 



3 



Z\ 



4 



Amplitude. 



16-1 

 0-6* 

 16-0 



15-8 



0-7 



15-7 



15-6 



0-8 



15-4 



15-2 

 0-85 

 15 -0 



14-8 



0-9 



14-6 



14-3 

 0-95 

 14-3 



14-1 

 1-0 



14-0 



log As=6-5059 



6-5271 



6-5477 



6-5439 



6-5426 



6-5434 



6-5427 ; flexure correction 



As=34-7xlO- 7 s>ec. 



* The values here given are the means of the values observed 10 seconds before and after the half- 

 minute. 



11 



