xii Proceedings of the Royal Society of Victoria. 



still under repair, the work of repolisliing the mirrors, after 

 twenty years' work, was commenced in May last, but the 

 preparations and practice landed us in the hot summer 

 weather before the operation was completed, and the work 

 had to be deferred till cooler weather prevailed, for polishing 

 cannot be attempted so long as we are subject to temperatures 

 of 80 to 90 and over. The work will be recommenced in 

 about a week, and if all goes well, I hope to have the 

 telescope at work again by Ma}-. 



Preparations have been pushed on for commencing the 

 international work of obtaining photographic charts of the 

 heavens, if possible, during the current year, but I fear that 

 the most than can be accomplished under the most favour- 

 able circumstances, will be "to get ready" to commence 

 early in 1890. The photographic telescope for Melbourne is 

 well advanced, and the building for its reception will be 

 erected shortly. In the meantime, many improvements are 

 being made in the methods to be adopted, and beautiful 

 photographs have been got of faint nebul?e and other objects 

 which have hitherto been considered " out of range " of the 

 sensitive film. 



The lunar tables hitherto used have been found insufficient, 

 and the most recent ones, viz., those of "Hansen's," after a 

 long period, it is found the tabular and observed places of 

 the moon differ very considerably, showing that some 

 disturbing causes have not been sufficiently allowed for in 

 their construction. Some yeai's ago. Sir George Airy (late 

 Astronomer Royal), then over 70 years of age, undertook 

 the development of a new lunar theory, a work of great 

 magnitude and mathematical intricacy. In November last, 

 he communicated to the Royal Astronomical Society, the 

 fact that he had discovered an error which had crept into 

 the earlier part of his work, that would necessitate attacking 

 it from the beginning, but that with advancing years (now 

 88) and failing strength, he could scarcely hope to bring it 

 to a satisfactory conclusion. It is to be hoped, however, 

 that some others will take up this important work, so 



