52 Anniversary Meeting. [Nov. 30, 



40-inch graduations on the scale ; but no exact comparison has 

 hitherto been made between the length of this portion of the scale and 

 the national yard, and such a comparison is no easy matter. It 

 happens that Commandant Deforges has been engaged in determining 

 the length of the seconds' pendulum at Greenwich with reference to 

 the French standard metre ; and just before his return to Paris he 

 came to our meeting, and offered to take charge of tho scale, bring 

 it with him to Paris, and there determine the length of the part of 

 the scale used by Kater and Sabine with reference to the metre, for 

 doing which he has all the requisite appliances ; and as we know the 

 ratio of the metre to the yard, the length of the seconds' pendulum as 

 determined by Kater and Sabine would thus be known accurately 

 with reference to the standard yard. It seemed to me that so im- 

 portant a scale should hardly be sent away, even though in the care 

 of so experienced a physicist, without the authority of the Council, 

 and without an outer case being made for its box, which there was 

 not time to get ready. The authority of the Council has since been 

 obtained, and it fortunately happens that one of the assistants at the 

 Greenwich Observatory is going to Paris, who will take charge of 

 the scale. Thus by the kind proposal of Commandant Deforges, we 

 may shortly hope to have an authentic comparison of the length of 

 the seconds' pendulum as measured by Kater and Sabine with the 

 standard English yard. 



At the time of the anniversary last year, some of the reports of the 

 observers who went to Grenada to observe the Total Solar Eclipse of 

 August, 1886, had been sent in, and I mentioned that it seemed 

 desirable, for convenience of reference at a future time, that the 

 different reports should come out together, instead of being published 

 in a scattered form, provided at least that the waiting for the later 

 reports should not cause too much delay. I regret to say that the 

 completion of the reports has been delayed in part by the illness of 

 one of the observers, but I have every hope that they will all be in by 

 Christmas, and I do not anticipate that any long time will elapse 

 before they will be in some form in the hands of the public. 



The time is well within our recollection when the occurrence of 

 the solar prominences seen in total eclipses first attracted the atten- 

 tion of astronomers, and when, for observations bearing on their 

 nature, we had to wait for the rare and brief glimpses which, clouds 

 permitting, were afforded by total eclipses. Now, however, thanks 

 to the method of observation devised independently by Lockyer and 

 Janssen, they may be studied at any time. It would obviously be a 

 great advantage if a similar study could be made of the corona ; for 

 though we cannot expect to obtain a picture of it equal to that which 

 may be got during a total eclipse, yet if a fairly good picture could be 

 obtained from time to time, we might thereby be enabled to learn 



