OBSERVATIONS AT CHRTSTCHURCH, 1913. 



Latitude =-- 43-31' 50" S. Longitude = 172 38' 09" E. 



This set of observations in 1913 was undertaken largely in the hope of getting a 

 more accurate value for '' g " at this spot. Profiting by the experience of the former 

 visit, the observations were this time made in the " magnetic variation " house in order 

 to do away with temperature troubles. This meant that the iron in the pendulum 

 apparatus was bound to disturb the action of the magnetometers. Notwithstanding 

 this, Mr. H. F. Skey, Director of the Observatory, not only gave permission, but also 

 actively helped in its installation in the magnetic variation house. 



In order that the magnetic work shoiild not be disturbed too much, it was decided 

 to dispense with a pillar altogether and to place the stand directly on the concrete floor. 

 The stand therefore rested on the three base plates for the levelling screws and these 

 were simply cemented to the floor with plaster of Paris. The clock " S.C." hung on 

 one of the concrete walls and was firmly wedged in place. Portable field telephones 

 permitted the proper numbering of the seconds to the observer at the transit instrument 

 some 60 yards away, in a manner exactly analogous to that used at Winter Quarters. 

 All current for light, telephones, etc., was furnished from a set of portable accumulators. 

 A small relay was used on a separate lead to the transit instrument, in order that the 

 ticks of the clock should always be audible at the other end of the telephone. 



Instead of the transit instrument used in the previous observations, a slightly 

 smaller one was kindly lent by Mr. Skey. This was set up on the concrete pillar which 

 had been erected by Mr. Skey for the first observations in 1910. A new fixed mark- 

 was made in the form of a small electric light screwed to a heavy wooden post well 

 buried in the ground about 150 yards from the pillar. 



In addition to the meridian transit observations made at Christchurch, Mr. C. E. 

 Adams undertook similar observations at the Hector Observatory, Wellington, in order 

 to guard against the possibility of cloudy weather. By the kindness of the telegraph 

 service, a through line was provided to Wellington for a short time twice a day, and 

 the beats of " S.C." were recorded on a chronograph at Wellington. 



As an additional precaution, " S.C." was rated several times daily against the 

 portable chronometer " E " which rendered such satisfactory service at Cape Evans, 

 and the portable observatory chronometer. 



The observations for time taken at Wellington by Mr. Adams are not given in 

 full, but stars were observed on the evenings of Feb. 28th, March 3rd and March 5th, 

 the probable errors on these days being 0-03, 0-04 and 0-03 sec., respectively. The 

 deduced daily rate of the Observatory standard was 0-77 sec. losing for the first period, 

 and 0-73 sec. losing for the second period. 



Through the medium of the tape and printing chronographs at Wellington, " S.C." 



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