54 Capt. E. H. HilJs and Mr. H. F. Newall. 



All the essential points of this programme were carried out The 

 actual time of each exposure was as accurately as can be ascer- 

 tained, 



2nd contact: 10, 8, -6, -4, 2,0, +2, +4, +6, +8, seconds. 

 3rd -3, -1, +1, +3, +5, +8, +10, seconds. 

 Corona : Spectroscope No. 1. Exposed 79 seconds from 21 100. 

 No. 2. 98 7-105. 



The second series did not begin quite as soon as had been intended, 

 and between the fifth and sixth exposures there was rather a longer 

 interval than between the others, owing to a slight mistake on the part 

 of the exposer. This is, however, of no consequence, as all the interest 

 centres about the photographs taken within 5 seconds of the 

 contact. 



The Corona Spectrum. A reproduction of the corona spectrum as 

 obtained by the two-prism flint spectroscope is given in Plate 2. It 

 is obvious that the photographic intensity of the continuous spectrum 

 fell off very rapidly on receding from the limb. No trace of it is 

 seen at a greater distance than 4'. 



Five strong bright lines of unquestionably coronal origin are to be 

 seen. Their wave-lengths, and relative intensities may be provision- 

 ally given as 



A (Rowland). Photographic intensity. 

 3987-0 5 



4233-5 10 



4360-0 3 



4567-9 8 



5316-9 8 



There are other fainter lines whose wave-lengths have not yet been 

 determined. 



Spectroscope No. 2, with the quartz train, gave a corona spectrum 

 stretching a considerable distance into the ultra-violet, but of feeble 

 intensity. A strong bright line occurs at X 3801 '0, and the lines 

 given above are also to be plainly seen with the exception of the 

 well known line in the green which was outside the plate. 



Spectrum of the limb. The two series of spectra of the limb con- 

 tain an immense amount of detail, and will take a considerable 

 time for complete examination. As an indication of the character 

 of the results obtained, reproductions of portions of the two spectra 

 taken at second and third contacts are given in Plate 3. 



As considerable interest attaches to the question of the connection 

 between the bright line spectrum of the limb and the solar spectrum, 

 a reproduction of the latter, taken with the same instrument is 

 appended. 



