OBSERVATIONS AT WELLINC4TON. 



MARCH, 1913. 



HECTOR OBSERVATORY. Latitude, 41 17' 03"9 S. Longitude. 174 46' 03"4 E. 

 Height above mean sea-level, 401 -5 feet. 



For the Observations at Wellington, Mr. C. E. Adams, the Government Astronomer, 

 kindly lent the use of an underground chamber below the Observatory, which had 

 once belonged to the old Fort in whose place the Hector Observatory now stands. With 

 the help of the Public Works Department, the alterations deemed necessary were made. 

 These consisted in the erection of a solid pillar of brick faced with concrete. This was 

 of 66 cms. side at the base, at the top of 47 cms. side, and of total height 51 cms. Rigidly 

 cemented to the top was a marble slab 2 inches thick and 66 cms. square. In addition, 

 a considerable amount of wiring was done by the Department, in order that electric 

 light might be used for illumination purposes, so as to keep the temperature as constant 

 as possible. Other wires were also laid to enable " S.C." to be compared by chronograph 

 with the Observatory standard. 



The pillar is 20-5 links south and 79-1 links west of the transit instrument. 



The pendulum stand stood on the pillar in a small room by itself, and was observed 

 from outside through a glass door with a small section of the glass removed. 



The clock " S.C." hung from a heavy wooden beam wedged between two parallel 

 walls, and was fastened below to a similar beam of wood. 



In the same passage as the clock was set up the flash apparatus, at a distance of 

 360 cms. from the pendulum mirrors. For making the flash the same arrangement 

 was used as in the Christchurch observations the same helium tube and a large Cox's 

 coil lent by Professor Laby. Professor Laby, in addition, supplied a number of storape 

 cells and other gear, and also gave much valuable assistance. 



The pendulum clock " S.C." was again used for the coincidences, and was compared 

 with the Observatory standard before and after each set of observations by means of 

 the Gautier printing chronograph belonging to the Observatory. 



Mr. Adams made the necessary time observations for rate of the standard, and 

 his covering report is given herewith : 



" Owing to the prevalence of wet and cloudy weather, no attempt could be made 

 to follow any systematic programme in the selection of time stars, but every 

 opportunity was taken to observe on every possible occasion, and all stars 

 observed have been used in the determination of the clock error. 



" In the least square solution, weights depending on the star's declination have 



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