ii Report of Observatory Committee. 



with 12 eye pieces, micrometers of the most improved construction, 

 &c, would cost £4,200. 



An extra speculum, in case of accident, and a polishing machine 

 would cost about £700 more. 



Secondly, a Transit Circle. 



For this we recommend an instrument having a telescope of about 

 five feet focal length and five inches aperture, with two circles three 

 feet in diameter, one roughly graduated for setting and clamping, the 

 other graduated to intervals of 5' and read by six microscopes. This 

 instrument, with all the necessary microscopes for reading, telescopes 

 for collimating, illuminating apparatus for wires and field, &c, 

 constructed by Messrs Troughton and Simms, would cost £800. 



The work to be done by the large telescope was fully explained on 

 a former occasion* ; the transit circle should be employed in deter- 

 mining the position of the southern stars with the same accuracy as 

 has been arrived at in the northern hemisphere. 



Another important service which it would render would be the 

 more accurate determination of the co-efficient and law of refraction, 

 by observations on the zenith distances of stars, taken in combination 

 with observations of the same stars in the observatories of the 

 northern hemisphere. 



As subsidiary instruments in the Astronomical Observatory, there 

 should be a sidereal time clock, a mean time clock, and a chrono- 

 meter. The cost of these would not exceed £150. 



As a record of the state of the atmosphere, at the time of every 

 observation, must be made, in order to determine the proper correc- 

 tion for refraction, the Astronomical Observatory should also be 

 provided with a standard barometer and a stand of thermometers : 

 and since a large part of the work of a meteorological observatory 

 would thus necessarily form part of the Astronomical Observatory, it 

 would require no addition to the staff of assistants if the set of 

 meteorological instruments were rendered complete, by the addition 

 of a self-registering anemometer, an ajmaratus for determining the 

 electrical state of the atmosphere, and a few minor instruments. 



No observations, so far as we are aware, have yet been made in 

 the colony for the determination of the electrical state of the atmos- 

 phere, and as there is reason to believe that this is intimately con- 

 nected with the prevalence of dust storms, and as it undoubtedly 

 exercises an important influence on the progress of vegetation, we 

 consider its examination of great importance. 



As regards the Magnetic Observatory, we beg to call to your recol- 

 lection the unparalleled exertion which was commenced many years 

 ago to ascertain the magnetic phenomena of the earth. 



* On presenting the Memorial, the Committee stated that since it had been 

 drawn up the mail had arrived, bringing a report of the meeting of the British 

 Association at Dublin this year, that the British Association were renewing 

 their application to the Imperial Government for the large Southern Telescope. 



