41 



her motion of revolution over the earth, and anything which 

 tends to reduce the effect of the earth's motion of revolution, 

 increases the excess of Yenus's motion, or hastens Venus in 

 her transit. So that towards the Equator, Venus is hastened 

 more or less by the effects due to the earth's rotation. And, 

 on the contrary, at every point in high latitudes, Venus is 

 retarded in her transit by rotation ; these circumstances 

 affect both transits diversely, 1874 and 1882." 



In the Astronomer Eoyal's report of the stations to be occu- 

 pied by different countries, for the transit, not a word is said 

 of Hobart Town, as being fixed upon by the Americans ; what 

 he said was, that they, the English, had abandoned Macdonald 

 Islands, as it is considered that the observations there will be 

 sufficiently provided for by the Americans and the German 

 parties. 



It is not however, therefore, certain that any expedition 

 will be sent to Tasmania, for the purpose of observing the transit 

 of 1874. It has been said that the Australian colonies can 

 provide means for observing the transit within themselves, and 

 so they can, where they have qualified observers to assist in 

 observing this rare and special phenomenon, which is the 

 very foundation of all astronomical researches ; for, until we 

 know the sun's distance, we can determine neither his bulk, 

 nor his weight, nor his proper relationship with the planets ; a 

 small error in the solution of this problem would also result 

 in the withdrawing from our knowledge the great power and 

 wisdom employed in the researches of solar physics. 



In the absence of other astronomers, with more ample and 

 different means for observing, the instruments in use at the 

 Private Observatory, with a few accessories that have been 

 added,are quite sufficient for the direct observation of the tran- 

 sit, or for obtaining longitude and local time. The difficulty 

 at present appears to be, finding suitable observers, who are 

 accustomed to the use of astronomical instruments. The only 

 volunteer at present, is Commander Bedwell, who, at the sug- 

 gestion of the Hon. Sir J. M. Wilson, wishes to take part 

 in the observation, and render what assistance he can, pro- 

 vided he is able to make arrangements to be in Hobart Town 

 at the time. 



