]u. 



248 PROCEEDINGS OF THE [Nov., 1890. 



On the 9th, he was Uke myself wholly unsuccessful in finding the planet ; but 

 on the following days continued his micrometer measures. The results of these 

 observations he published in Am. Jour, of Sci.and ^rfe, for Jan., 1875, with 

 the amount of refraction in the atmosphere of Venus, deduced from his obser- 

 vations, and also Madler's formulae by which it was deduced. 



In Dec, 1882, the weather was so unfavorable on the day of the transit, the 

 6th, and for several days preceding and following, that I made no attempt to 

 observe it before and after conjunction ; and no accounts of the observations 

 of others have reached me ; but the scientific periodicals to which 1 have access 

 are so few, that it would be unwarrantable to say that none have been made. 



The next opportunity for observation will occur 8 years less 2^ days after 

 the last transit, that is on the 3rd of Dec. next, when the least distance on 

 centres will be about 35', at about 18 hours Greenwich mean time. As Venus 

 will pass south of the Sun, it will not be so easy to use buildings as screens, in 

 the northern hemisphere, and special means must be devised. The luminous 

 ring will be as bright and conspicuoas as in 1866, and the first appearance on 

 the prolongation of the cusps, may be looked for, about ^the 24th of Nov. 



It is now evident that similar opportunities will happen on 1st of Dec, 1898, 

 when least distance of centres will be about 1°, and about 28th of Nov., 1906, 

 when least distance of centres will be about 1^°, the planet in both cases 

 south of the Sun. In each case the least distance of centres will be less than 

 the limit within which the formation of the luminous ring is possible, but the 

 duration of the ring, will be successively less, as the least distance between 

 centres becomes greater. No other opportunities will present themselves, until 

 near the end of the next centur}^ when they will occur in June. 



Similar opportunities must have occurred in years preceding 1866, that is of 

 14th of Dec, 1858, and also on 16th of Dec., 1850, but it does not appear that 

 either was used. This last date is only nineteen months after Madler's obser- 

 vations in May, 18 49, and if any one properly situated as to time, had endeav- 

 ored to repeat Madler's observation on the day of conjunction, he would almost 

 certainly have seen the luminous ring. 



A letter of resignation from Dr. C. W. KoUock was read and the 

 Treasurer was requested to endeavor to induce its withdrawal. 



Member Elected. 

 Mr. H. A. M. SmTH. 



