1882.] On the Recent and Coming Total Solar Eclipses. 297 



totality as the air was gradually darkened, by which darkening 

 successive veils, as it were, were lifted so that the more delicate 

 phenomena could be successively seen. 



Fig. 5. 



16. We begin with one short and brilliant line constantly seen 

 in prominences, never seen in spots. Next, another line appears, also 

 short and brilliant, constantly seen in prominences, and now, for the 

 first time, a longer and thinner line appears, occasionally noted as 

 widened in spots, while last of all we get very long, very delicate 

 relatively, two lines constantly seen widened in spots, and another 

 line not seen in the spark and never yet recorded as widened in the 

 spots. 



17. The procession from the hot to the colder is apparent, and the 

 simplicity of the spectrum as opposed to the Fraunhofer spectrum 

 even yet, is eloquent of the gradual approximation which would be 

 still possible if the darkness could be greater and our attack more 

 complete. 



18. It will be noted over what an excessively small range the 

 observations extend. We want similar observations over a wider 

 range during future eclipses, and to do this work properly many 

 observers armed with similar instruments must divide the whole or 

 part of the solar spectrum amongst them, preferably that part 

 between F and D, which has been most closely watched in pro- 

 minences and spots by Tacchini and myself. 



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