196 KETIEWS — U. S. NATAL ASTEONOMICAL 



that the principal assistant must be temporarily released, or be broken down 

 perhaps permanently. The opportunity to send him to Valparaiso for the 

 meridian circle, "was therefore a welcome one. Messrs. Hunter iind Smith, record- 

 ed for me on alternate nights, until the former was disabled by being thrown 

 from a horse All the aid was then from Mr. Smith ; besides which duty, he 

 became wholly charged with the meteorological observations for every third hour, 

 between six, a., m., and midnight. Within the forty-eight working nights em- 

 braced between the above dates, nearly 1400 observations of the planet were 

 accumulated; and by the time that this series terminated, the piers for the 

 meridian circle were finally completed, the health of Lieut. MacRae re-established, 

 and we were able to give undivided attention to its erection and adjustment ; so 

 that the instrument was ready for use about the middle of February. 



But it must not be inferred that our nights from the 31st of January, were 

 passed idly. Observations for approximate place of the circle had commenced 

 some days before, and extra hours of every night were spent in becoming 

 familiar with the details of the superb instrument that Messrs. Pistor and Martins 

 had sent us from Berlin ; and thus, by the time its adjustments were rjerfected, 

 both of us were expert in its manipulation. Beginning within 5° of the south 

 pole, a systematic sweep of the heavens was then commenced iu zones or belts, 

 24' wide. Working steadily towards the zenith on successive nights, until com- 

 pelled to return !;elow again to connect in right ascension, the place of every 

 celestial body that passed across the field of the telescope, to stars of the tenth 

 magnitude, was carefully noted down. The space immediately surrounding the 

 south pole, was swept in one belt of 5° by moving the circle, and each zone 

 overlaps those adjoining both in right ascension and declination. Above the polar 

 belt there are forty-eight others, making in all 24 12' of declination, within which 

 we obtained 33,600 observations of some 23,000 stars, more than 20,000 of them 

 never previously tabulated. * * * * 



From Oct. 1S50, Messrs. Macftae and Phillip had the entire charge of the instrument 

 for zone observations. When an accident to one of the screws compelled the 

 services of both at the same time, until a new one was received from Berlin, I de- 

 voted every other night to the examination of the stars in the catalogue of Lacaille, 

 and between the zenith and our upper zone, which had never been reobserved. 

 ***** As may be supposed, the discrepancies 



between our estimations of the magnitudes of stars, and those of preceding 

 observers were very considerable in a multitude of cases ; but we endeavoured to 

 preserve an uniform system, and will reconcile discordances it we can. There were 

 many errors in Laeaille's work, at the Cape of Good Hope, and quite a number 

 of his stars do not exist in the reduced places of the British Association publica- 

 tion ; but we were only amazed that he should have been enabled to accomplish so 

 much, and so well, with a telescope only half an inch in diameter, and in the brief 

 space of ten months. 



It was a great satisfaction to work with an instrument like ours, but there was 

 almost too much of it. Out of 132 consecutive nights, after the equatoreal was 

 mounted, there were only seven cloudy ones ! Of necessity, to afford so large a pro- 

 portion, the air must be exceedingly destitute of moisture, a condition of things 

 favorable to telescopic vision, but not so to eyes employed during prolonged 

 observations. 



