118 



Mr. J. N. Lockyer. 



[Nov. 17, 



(1.) The luminous phenomena, not only of comets, as determined 

 on other grounds by Schiaparelli, but of all bodies in the heavens 

 shining by their own light, except stars like the Sun and Sirius, are 

 produced by meteorites in various aggregations and at different 

 temperatures. 



(2.) The temperature of the meteorites in some cases is about that 

 of the oxyhydrogen flame. 



(3.) Among the chief sources of fluting absorption in many " stars " 

 are manganese vapours at a low temperature. 



(4.) The bright flutings of carbon in some " stars," taken in con- 

 junction with their absorption phenomena, indicate that widely 

 separated meteorites at a low temperature are involved. 



(5.) Olivine and kindred minerals appear to be chief bright-line- 

 producing agents in the " nebulae." 



(6.) New stars are produced by the clash of meteor swarms, the 

 bright lines seen being low temperature lines of those elements in 

 meteorites the spectra of which are most brilliant at a low stage of 

 heat. 



(7.) The spectrum of the hydrogen in the case of the nebulas seems to 

 be due to low electrical excitation, as happens with the spectrum of 

 carbon in the case of comets. Sudden changes from one spectrum to 

 another are seen in the glow of meteorites in vacuum tubes, when a 

 current is passing. 



Addendum. Received November 15, 1887. 



In anticipation of the detailed account and maps which are now 

 being prepared, I beg to append a brief statement showing the line of 

 investigation adopted, and how the various intercomparisons of labor- 

 atory and observatory work which have suggested the above general 

 views have been made. 



Experiments upon which the foregoing Conclusions depend. 



A. Experiments upon Carbon. 



The main conclusions which may be stated here are that there are 

 two systems of flutings which depend upon temperature only. At low 

 temperatures all compounds of carbon give a set of simple flutings, 

 the brightest of which are at wave-lengths 4510, 4830, 5185, and 

 5610. At higher temperatures there is a series of compound flutings, 

 the brightest edges of which are at wave-lengths 4380, 4738, 5165, 

 and 5640. In the case of compounds of carbon with hydrogen, there 

 is an additional fluting at wave-length 4310, and this is the only 

 criterion for the presence of hydrocarbons among the flutings shown on 

 the map (see Map 3). 



