Report of the Keiv Committee. 407 



HjdromBters 512 



Anemometers 15 



Rain Gauges , 6 



Sextants 139 



Index and Horizon Glasses, unmounted ......... 170 



Dark Glasses, unmounted 597 



Theodolites 9 



Besides these, 32 Deep-sea Thermometers have been tested, 16 of 

 which were subjected, in the hydraulic press, without injury, to 

 pressures exceeding two tons on the square inch. 27 Thermometers 

 have been compared at the freezing-point of mercury, making a total 

 of 11549 for the year. 



Duplicate copies of corrections have been supplied in 84 cases. 



The number of instruments rejected on account of excessive 

 error, or which from other causes did not record with sufficient 



accuracy, was as follows : — 



Thermometers, clinical 67 



,, ordinary meteorological 49 



Various 112 



7 Standard Thermometers have also been calibrated, and supplied 

 to societies and individuals during the year. 



1 Redier Barograph, 1 Richard Hygrometer, 1 Air Meter, 2 Tele- 

 scopes, &c, were also examined. 



There are at present in the Observatory undergoing verification, 

 43 Barometers, 904 Thermometers, 2 Hydrometers, and 27 Sextants. 



A question having arisen as to the true interpretation of the tables 

 of Specific Gravity used in connexion with the verification of instru- 

 ments of the hydrometer class, a Sub-Committee has been appointed 

 to consider the matter and authorize the adoption by the Observatory 

 of certain definite rules. 



VI. Rating of Watches. 



The arrangements for rating watches mentioned in previous 

 Reports have been continued during the year with great success, and 

 up to the present 834 watches have been examined, of which 16 were 

 submitted by the owners, and 818 by the manufacturers or dealers. 



490 watches were received as contrasted with 302 received during 

 the corresponding period of last year. They were entered for testing 

 in the following classes : — 



For class A, 436; class B, 36; and class C, 18. Of these 148 

 failed to gain any certificate ; 16 passed in C, 102 in B, 224 in A, and 

 8 obtained the highest possible form of certificate, the class A especially 

 good. 



