320 



Report of the Keiv Committee. 



Hydrometers 461 



Anemometers 14 



Rain Gauges 20 



Sextants 130 



Index and Horizon Glasses, unmounted 74 



Dark Glasses, unmounted 235 



Besides these, 38 Deep-sea Thermometers have been tested, 32 cf 

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

 pressures exceeding two tons on the square inch. 55 Thermometers 



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

 of 10,361 for the year. 



Duplicate copies of corrections have been supplied in 43 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 52 



„ ordinary meteorological 4 



Various 97 



3 Standard Thermometers have also been calibrated, and supplied 

 to societies and individuals during the year. 



1 Evaporation Gauge, 4 Thermograph Thermometers, 1 Sunshine 

 Recorder, 2 Gauge Barometers for comparing Aneroids, 1 Electrical 

 Anemometer, and 1 Richard Thermograph were also tested. 



There are at present in the Observatory undergoing verification, 

 2 Barometers, 222 Thermometers, 100 Hydrometers, 24 Sextants, and 

 1 self-recording Aneroid. 



Sextant Testing Apparatus. — In consequence of the increasing 

 number of sextants sent to the Observatory for examination it was 

 found desirable to provide a special accommodation in the building 

 for the work. As the room known as the Pendulum room was 

 unoccupied, and the masonry pier fitted up in it as a support for 

 pendulum apparatus was no longer required, it was resolved to 

 convert the apartment into a sextant room, and accordingly the pier 

 was removed, and the Cooke testing apparatus dismounted from the 

 South Hall and re-erected on its site. Four careful redeterminations 

 were then made of the angles between the collimators, and they 

 were found to have been unaffected by the transfer of the apparatus 

 to the new position. 



VI. Rating of Watches. 



The arrangements for rating watches mentioned in previous 

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



