590 Transactions. 



Art. LV.- — The Longitude, Latitude, and Height of the Hector Observatory, 



Wellington, New Zealand. 



By C. E. Adams, D.Sc, F.R.A.S., Government Astronomer of the 



Dominion of New Zealand. 



[Rend before the Wellington Philosophical Society, 28th October. 10 N.} 



(A.) Longitude. 



1. In 1883 the difference of longitude between the Sydney Observatory, 

 Australia, and the Mount Cook Observatory, Wellington,* New Zealand, 

 was determined by means of the electric telegraph. The late Mr. H. C. 

 Russell, Government Astronomer of New South Wales, observed at Sydney, 

 and Mr. C. W. Adams, Geodesical Surveyor, observed at Wellington. The 

 difference of longitude was found to be lh. 34m. 16 - 984s. + 0-020s.f 



2. A point 198-38 links due north of the Mount Cook Observatory is the 

 initial point of New Zealand surveys. J 



3. From this origin, and on the meridian of Mount Cook, the co- 

 ordinates of the Bolton Street Observatory and of the Hector Observatory 

 have been determined by Mr. J. D. Climie, Inspector of Surveys, Lands 

 and Survey Department. These co-ordinates are, — 



Mount Cook initial 



Bolton Street Observatory, transit instrument 



Hector Observatory, transit instrument . . 



4. From the co-ordinates in 3 the differences of longitude, latitude, 

 and azimuth have been calculated, using Clarke's 1880 Spheroid and Tables 

 of Geodetic Factors, || with the following results : — 



Mount Cook initial - Bolton Street Ob- 

 servatory 

 Mount Cook initial - Hector Observatorv 



* For the information of readers who have no local knowledge of New Zealand, it 

 ought to be stated that the " Mount Cook Observatory " was demolished shortly after 

 the observations were made in 1883, and a gaol built on the site; it was situated on a 

 small knoll in the southern part of Wellington City, and had no connection with 

 "Mount Cook," the highest mountain in New Zealand (12,349ft. high). 



t C. W. Adams : " Report on the Surveys of New Zealand for the Years 1883-84," 

 Appendix No. 1, p. 3. Wellington : George Didsbury, Government Printer, 1884. 



J Plan of Mount Cook Observatory, Wellington, in above report. 



§In Trans. N.Z. Inst., 1902, vol. 35, p. 441, Mr. Thos. King quotes 2097-2 links 

 west. This was the position of the dog-vane on the Bolton Street Observatory, and 

 not that of the transit instrument. 



|| C. E. Adams : Rep. Aust. Ass. Adv. Sci., p. 93, 1904; Dunedin. 



