248 REPORT— 1875. 



stage of the operation was found on analysis to consist of hydrogen, carbonic 

 oxide, and carbonic acid, the latter amounting to three or four per cent. 



In some experiments on artificial soft iron the author obtained a spectium 

 in every way similar to that of the meteoric metals ; the hydrogen lines did 

 not appear so early nor were they so bright as in the latter instances. 



The iron of this meteorite, which by its great hardness was separated in 

 the state of fine powder, yielded, when heated at different temperatures up to 

 low redness, 44 times its volume of gas. While it seems not improbable that 

 some portion of what has been occluded gas may have been atmospheric air, 

 the yield is so unusually large that it suggests the question, May not the more 

 perfect removal of the gas from the iron be due to the fine state of division of 

 tlie metal operated upon? In the case of the Texas and Tazewell irons, 

 Avhere the yield of gas exceeded that obtained from the Lenarto and Augusta 

 Co. irons, the metals were in very small pieces, which would favour a more 

 refined and complete evolution of the gas ; in the last-mentioned instances 

 they were en bloc. That iron may under certain conditions, as when deposited 

 by electrolysis, take up nearly two hundred and fifty times its volume, has 

 been shown by the recent researches of M. Cailletet*. An observation re- 

 cently made has a bearing on this question, "WhUc analyzing a specimen of 

 silver amalgam, I endeavoured to remove from a weighed fragment of tho 

 mineral the mercury by heating the specimen in a hard glass tube for more 

 than five minutes in the flame of the table blowpipe. The silver immediately 

 fused and remained during that time in a molten state. When cold, the 

 globule of metal was flattened into a plate, and having cut it into strips and 

 subjected it to a second heating, I succeeded in removing a considerable part 

 of a per cent, of mercury from it. 



Wright's researches on the gases of meteoric irons have shown a varying 

 character in theox}-gen and nitrogen lines when in the presence of hydrogen, 

 and the near coincidence of two of them with prominent lines in the corona, 

 with the possible coincidence of a third line, which appears to indicate that 

 the characteristic lines in the coronal spectrum are due, not so much to the 

 presence of otherwise unknown elements, as to hydrogen and the atmospheric 

 gases oxygen and nitrogen. 



The observations were made with a spectroscope of six prisms with a re- 

 peating prism, giving the dispersion of twelve in all. 



1853. — Tazewell, Claiborne Co., Tonnesseef. 



This meteorite was one of those selected by the author for his investigation 

 with the spectroscope of the gases occluded by meteoric iron (see also the 

 meteorites of Eed Eivcr, Texas, and Arva, Hungary). It is noted for the 

 large amount of nickel, 14-62' per cent., which it contains; it had been exa- 

 mined by J. L. kSmith %, who found no carbon in it. As in the case of the 

 Texas meteorite, this iron appears to evolve gas before heat is applied ; the 

 red and green hydrogen lines were brilliant, while the bands of carbon were 

 not noticed. When heat was applied, the spectrum showed the hydrogen 

 lines very brilliantly, and the four chief carbon bands in great strength. As 

 the tension of the gas decreased, the hydrogen lines became relatively stronger, 

 and the carbon bands grew narrower ; and at 1 milUm. these bands were still 

 prominent, and some narrow bands, apparently belonging to nitrogen, were 



* L'Institut, uouv. sir. iii. p. 44. 



t A. W. Wright, Amer. Journ. Sc. 1875, is. p. 204. 



I Amcr. Jouru. go. [2], vol. sis. p. 153. 



