PHOTOGRAPHS OF THE CORONA. 107 



following times from the commencement of totality : 6, 16, 

 36, 66, 96, and 111 seconds. The last plate in each camera was 

 spoiled by the return of sunlight. 



It will be seen at once that this programme involved that 

 many of the photographs would be valuable only as a guide to 

 future work. Nevertheless, one taken with the Waters on an 

 Ilford extra rapid plate, exposure 5 seconds, and three with 

 the stigmatic lens, are exceedingly successful as photographs. 

 The Waters plate shows a remarkable amount of detail for so 

 small an aperture and so great a magnification ; and the three in 

 the 9-in. camera show the coronal streamers farther than they 

 have ever been photographed before. 



A thirteenth plate was exposed in the 9-in. camera about 

 forty seconds after the return of sunlight. The plate was a 

 triple-coated Sandell, and the exposure was for 1 \ seconds. It- 

 shows the inner corona perfectly distinctly, and the whole of the 

 black disc of the moon is clearly defined, whilst the crescent of 

 sunlight is reversed and strongly solarised. It may be noted 

 that this " carraway seed " of solar light was seen distinctly 

 impressed upon the plate before development was commenced, 

 and yet the corona can be traced round till it almost meets the 

 solar crescent. This is the first time that the corona has been 

 unmistakably photographed in the presence of so much sunshine. 



The plates used were of three kinds. Two were Hill Norris' 

 dry collodion Eagle plates. These gave practically no result. 

 Six were Ilford red label extra rapid, and were developed with 

 hydrokinone, the development being restrained and prolonged. 

 The best plate taken with the Waters was one of these. Four 

 were Sandell triple -coated, and two of these show the long rays 

 much farther than any of the others. Their development was 

 by hydrokinone and metol. 



ANNIE S. D. MAUNDER. 



I used a Dallmeyer rapid rectilinear lens of 1 in. aperture 

 and 11 in. focal length, and exposed a single Ilford plate for 

 \ second, which I developed with " hintokinone. The plate is 

 fully exposed, and shows a dense image of the corona. 



A. E. OAKES. 



I used a Watson's Alpha camera for 5 by 4 plates with a 

 rapid rectilinear lens J in. in diameter, and focal length about 

 5J in., a stop of //1 6 being used. I exposed two plates, Ilford 

 special rapid, which I developed with hydrokinone and 

 eikonogen. The exposure of the first was for 3 seconds, the 

 second 25 seconds. The shorter exposure was ample, and that 

 plate is much better than the other. 



F. LYS SMITH. 



