xvi President's Address 



Our National Museum already shows signs of being 

 cramped for room, and the director (Professor M'Coy) during 

 the past year has directed his attention to additions of such 

 classes as occupy small space, and has therefore devoted his 

 work chiefly to the zoological and geographical classification 

 of insects, and in filling up gaps in the collection of shells. 

 Important additions have also been made to the collection 

 of fishes by numerous specimens of both Australian and New 

 Guinea species. 



Our Observatory has continued its accustomed work in 

 astronomy, meteorology, magnetism, &c. The year has been 

 marked by one or two interesting astronomical events; which 

 have varied the monotonous routine of observation. First, 

 the apparition in September of the Great Comet of 1882 ; 

 then the Transit of Yenus in December; and subsequently 

 the determination by telegraph of the differences of longitude 

 between Singapore and Port Darwin, and then between Port 

 Darwin, Adelaide, Melbourne, and Sydney. The two first 

 occurrences I shall refer to presently. 



In my last address I referred to preparations being made 

 for the telegraphic determination of longitude between 

 Greenwich and Australia. Hitherto all Australian longitudes 

 have depended upon observations of the transit of the moon 

 and fixed stars near her path, known as moon culminations, 

 compared with similar observations made at Greenwich on 

 the same day, extensive series of which were obtained many 

 years ago at Williamstown, and afterwards at our present 

 Observatory, as well as the Sydney Observatory. This, 

 although the most accurate of all- purely astronomical methods, 

 is not so accurate as that by actual transmission of time 

 signals or clock beats by telegraph from one observatory to 

 another. Of course, the best way to use the latter method 

 would be for Greenwich Observatory to send its clock ticks 

 direct to Adelaide, Melbourne, and Sydney, and then each 

 of these to do the same to Greenwich, the clocks being cor- 

 rected to true local time ; the differences of the times in 

 each case would give the difference of longitude, affected only 



