Anniversary Address. xxix. 



The result of the observations of the transit of 1874 cannot be 

 regarded as satisfactory; for, whilst Sir George Airey, in his official 

 report, stated the solar parallax as 8' 76" — corresponding to 93,375,000 

 miles — Colonel Tupman and Mr. Stone, from the very same observa- 

 tions, deduced the parallax respectively as S^Sl" and S^". The 

 agreement to within the tenth of a second of arc in angular measure 

 seems, at first sight, very close ; but, so vast is the distance represented 

 in the solar parallax by that fraction, that these three calculations 

 differ to an extent considerably exceeding a million of miles. 



The observations of the transit of Venus of last year were under- 

 taken by all civilized nations with the same zeal and interest that 

 characterized the efforts of 1874. On this occasion the British 

 astronomers discarded photography, whilst the Americans relied greatly 

 on that means of observation. 



In New Zealand the egress alone cou'ld be seen, and was observed 

 from thirteen stations by seventeen scientific gentlemen, amongst 

 whom were Dr. Hector, Mr. McKerrow, and Archdeacon Stock. 

 There were also an English party of observers, near Christchurch, 

 under Colonel Tupman, and an American party at Auckland, under 

 Mr. Edward Smith, of the United States Coast Survey. The 

 Government assisted liberally both by grants of money and by placing 

 the Telegraph Department at the disposal of the observers. Unfor- 

 tunately, Dr. Hector's observation at Clyde was partially intercepted 

 by a cloud, but, with the exception of this contretemps, the observa- 

 tions in New Zealand were entirely successful. I cannot but remark 

 that it reflects great credit on the colony that so many gentlemen 

 should have voluntarily engaged in this work; and I have no doubt 

 that, when the report of the results of the British expeditions are 

 published, their services will receive cordial acknowledgment. 



The observations of last year's transit throughout the world were 

 attended with thorough success, and it is expected that, when the 

 calculations have been completed, a great step will be made 

 towards reconciling the conflicting results that have hitherto been 

 obtained. But, before the question can be finally set at rest, the 

 results of the observations on the transit of Venus must be reconciled 

 with those obtained by other methods, which it would be out of place 

 for me now to discuss. 



Judging, however, from the conclusions already derived from 

 various independent calculations, it seems probable that the true 

 distance of the earth from the sun will be found to be between 

 ninety-two and ninety- three millions of miles. 



Meanwhile the scientific world awaits with the greatest interest 

 the calculations of astronomers on this vital problem. The impor- 

 tance of it is not merely to be regarded as one which concerns 



