78 J. Waterhouse — Photography in connection with [No. 2, 



this two six-inch plates were exposed and then, about bisection, another 

 Janssen, followed by two more six-inch plates and then a third Janssen for 

 the first internal contact, for the exposure of which a signal was to be given 

 by Colonel Tennant. Owing to the wet plate prepared for this having 

 slipped off the dipper, a dry plate was substituted and the plate was mounted 

 in ample time. While watching the image carefully through the red glass, 

 waiting for Colonel Tennant's signal, I noticed that the planet appeared to 

 have passed well within the boundary of the solar disc, though still attached 

 to the limb by a well and strongly defined ligament, so that the planet and 

 ligament were of a distinct gourd -shape exactly like the appearance of the 

 " black drop" one had been led to expect.* On development the plate 

 showed no sign of any such such gourd-like appearance, except at the 21st 

 picture where the clock-work had dragged, and there an image appeared, 

 the exact counterpart of what I had seen. 



After this the regular work with the six-inch plates commenced and 

 went on pretty regularly, at the stated intervals of two minutes between 

 each exposure, till about half-past 9, when there was a break of 15 minutes 

 for refreshment and to change the chronograph paper, &c. 



Though this break may appear long, it had been found more convenient 

 to have one long break than two or three shorter ones, on account of the 

 loss of time in stopping and getting under way again. It was arranged 

 that the break should take place either well before or after mid-transit, so 

 as to be sure of pictures being taken about the time of mid-transit. 



It was also arranged that when the signal for the break was given, all 

 wet plates under preparation should be exposed and dry plates sent in till 

 all the wet plates had been developed and every thing was ready for open- 

 ing out the doors. In the same manner after the break, dry plates were 

 sent in until the wet plates were ready. The work then went on as before 

 till the time came for mounting the Janssen for the second internal contact, 

 which was exposed by signal from Colonel Tennant. Two more six-inch 

 plates were then taken, then a Janssen, followed by two more six-inch plates, 

 and last of all a Janssen, about the time of last contact, which was exposed 

 and closed a few seconds before the final contact, tlras concluding the work. 



The sequence of the plates in the racks was examined and the plates 

 were left to dry till next day and then replaced in the plate boxes. 



It had originally been intended that 120 six-inch plates should be 

 taken, as it had been found quite possible to do so at the rehearsals, but as 

 I was perfectly dependent on Colonel Tennant's signals for starting the 

 Janssen plates, I allowed plenty of time so as to make sure of having the 



* Colonel Tennant remarks with reference to this — " There is no doubt in my mind 

 that the outer part of the sun is never free from the result of outstanding astigmatism. 

 For Janssen plates it should have been specially cared for at the expense of the central 

 portion of the picture." 



