Totnl Eclipse of the Sun, May 28, 1900. 34:5 



ness in regions other than those where the chromospheric ares are 

 brightest. As before, 3987 '0 is much more uniform in brightness 1 

 throughout the extent of the ring than the others ; 5303 - 7 is especially 

 strong in one or two regions ; but on the whole is probably weaker 

 than in 1898. 



The photographs show that the scale of the spectra is by no means 

 too large for work with short exposures with a lens of 6 inches aper- 

 ture. The spectra are 7*5 inches long from D 3 to K, and the diameter 

 of the rings is 2'5 inches ; photographs taken with an exposure esti- 

 mated at of a second are fully exposed. 



The Differences between tlie Coronas observed at the Periods of Sun-spot 

 Maxima and Minium. 



My attention was called especially to these differences, because I 

 saw the minimum eclipse of 1878, while the phenomena of that of 

 1871 (maximum) were still quite fresh in my mind. My then pub- 

 lished statements have been amply confirmed during the eclipses which 

 have happened since 1878, but certainly the strongest confirmation 

 has been obtained during the present one, which took place two more 

 spot periods after 1878. 



1. Form. 



"With regard to form, at the instant of totality I saw the 1878 

 corona over again, the wind vane appearance being as then most 

 striking. 



2. Tlie Spectrum. 



In connection with the eclipse of 1878 (minimum), I pointed out 

 that, whereas in 1871 (maximum) the spectrum of the corona viewed 

 by small dispersion was remarkable for the brightness of the lines ; in 

 1878 they were practically absent, and the continuous spectrum was 

 remarkably brilliant. 



I determined therefore to make a similar observation in this year of 

 maximum, and, as in 1878, used a grating first order spectrum placed 

 near the eye. The result was identical with that recorded in 1878. I 

 saw no obvious rings or arcs, but chiefly a bright continuous spectrum. 



3. Tlie Minute Structure of the Inner Corona. 



Lieut. Doughty, E.N., and myself made observations on the minute 

 structure of the corona, in order to see if any small details could be 

 observed, and whether they were the same as those I saw so well and 

 recorded during the eclipse of 1871, at a period of sun-spot maximum. 

 This question was specially taken up this year, as exactly two sun- 

 spot periods have elapsed since 1878. 



2 c 2 



