380 MEETING OF THE BRITISH ASSOCIATION. 



NEW FORM OF CARBURETTED HYDROGEN. 



Before dismissing the subject of coal, it may be proper to notice 

 the recent discovery by Berthelot of a new form of carburetted 

 hydrogen possessing twice the illuminating power of ordinary coal 

 gas. Berthelot succeeded in procuring this gas by passing hy- 

 drogen between the carbon electrodes of a powerful battery. Dr. 

 Odling has since shown that the same gas may be produced by 

 mixing carbonic oxide with an equal volume of light carburetted 

 hydrogen and exposing the mixture in a porcelain tube to an in- 

 tense heat. Still more recently, Mr. Siemins has detected the 

 same gas in the highly-heated regenerators of his furnaces, and 

 there is now every reason to believe that the new gas will become 

 practically available for illuminating purposes. Thus it is tha* 

 discoveries which in the first instance interest the philosopher only, 

 almost invariably initiate a rapid series of steps leading to results 

 of great practical importance to mankind. In the course of the 

 preceding observations I have had occasion to speak of the sun as 

 the great source of motive power on our earth, and I must not 

 omit to refer to recent discoveries connected with that most glorious 

 body. 



MATERIALS OF WHICH THE SUN IS MADE. 



Of all the results which science has produced within the last 

 few years, none has been more unexpected than that by which we 

 are enabled to test the materials of -which the sun is made, and 

 prove their identity, in part at least, with those of our planet. The 

 spectrum experiments of Bunsen and KirchhofF have not only 

 shown all this, but they have also corroborated previous conjec- 

 tures as to the luminous envelope of the sun. I have still to ad- 

 vert to Mr. Nasmyth's remarkable discovery, that the bright sur- 

 face of the sun is composed of an aggregation of apparently solid 

 forms, shaped like willow-leaves or' some well-known forms of Dia- 

 tomacese, and interlacing one another in every direction. The 

 forms are so regular in size and shape- as to have led to a sugges- 

 tion from one of our profoundest philosophers of their being or- 

 ganisms, possibly even partaking of the nature of life, but, at all 

 events, closely connected with the heating and vivifying influences 

 of the sun. These mysterious objects, which, since Mr. Nasymth 

 discovered them, have been seen by other observers as well, are 

 computed to be each not less than 1,000 miles in length and about 

 100 miles in breadth. The enormous chasms in the sun's photo- 



