Annual Address to the Members. xlvii 



tions were not reduced, but that so large a mass of work was actually 

 done. In this respect Maclear was not fairly treated, but he did his 

 best under the circumstances, and no man could do more — few, 

 indeed, would have done as much. He was also carrying out, at the 

 same time, a long series of observations on the bright star Alpha 

 Centauri, to test or confirm Henderson's result for the parallax of 

 that star. 



It is an instance of the sanguine and energetic temperament of the 

 man that he could, in addition to these absorbing occupations, turn 

 his attention — not as a separate work, but as a work superadded 

 to the labours of the Observatory — to the measurement of an arc of 

 meridian. In 1838 the first part of this great work, " The Verification 

 of Lacaille's Arc of Meridian," was commenced. The measurement 

 of this arc and its extension were commenced in 1840, and the field 

 work was finished in 1847. It is impossible to convey within the 

 limits of this address an adequate idea of the indomitable energy 

 and perseverance with which this operation was carried out, of the 

 difficulties surmounted, and of the extent and value of the work 

 accomplished with limited means. That all this was fully recognised 

 at the time is sufficiently testified by the fact that for this work he 

 received the gold medal of the Eoyal Society of London, and the 

 Lalande medal of the Institute of France. 



In 1847 a 46-inch achromatic telescope by Dollond was mounted 

 equatorially, and in 1849 an equatorial by Merz, of 7 inches aperture 

 and 8^ feet focal length, was added to the instrumental equipment of 

 the Observatory. These instruments were vigorously employed in 

 the observation of double stars, comets, and nebulae, and of occult- 

 ations of stars by the moon. The original records show that the 

 observations were sustained nearly all night long, and contain 

 frequent notes to the effect that the watch had been brought to a 

 close by the rising sun. All comets visible in the Southern 

 Hemisphere were diligently observed by Maclear, and the results of 

 the observations promptly published through the Koyal Astronomical 

 Society. Simultaneously with these observations, the meridian 

 instruments were worked with redoubled energy, and during the 

 years 1849-53 the whole of the stars in the British Association 

 Catalogue having ^outh declination were observed generally three 

 times in each co-ordinate. The energy with which this series of 

 observations was carried on is shown by the fact that in 1852 between 

 9,000 and 10,000 observations of right ascension were made with the 

 transit instrument ; on some nights over 100 stars were observed. 

 These observations, in form of the " Cape Catalogue for 1850," have 

 been published by the present astronomer. In 1855 the new transit 



