OBSERVATIONS OP LTTMINOUS METEORS. 247 



respect ho is acquainted with ouly three or four irons which rival it. Au 

 iUustration accompaujdug his paper, closely resembling the one given by Troost, 

 is a representation of the outer surface magnified ; this is elaborately reticu- 

 lated, edges of thin lamiua3 of metal, inclined at angles of 60°, traversing the 

 surface, the edges being separated from each other by au apparently semi- 

 fused slag-like material. The specific gravity of the iron is 7-717, and its 

 composition ; — 



Iron =:9M5, Nickel =8'01, Cobalt =0-72, Copper =0-06 : total 99-94. 



Sulphur is not present, and of phosphorus only a trace was recognized ; and 

 the author states that he has never before met with so small a proportion of 

 this element in a meteoric iron. The gas extracted from this iron by A. W. 

 AVriglit, who has recently examined the occluded gases of the irons of Texas, 

 Arva, and Tazewell Co., as well as that of the meteorite of West Liberty, Iowa 

 (which sec), has nearly twice the volume of the metal operated upon, although 

 this is probably a portion only of that actually present. It is composed of : — 



Hydrogen =71 '4, Carbonic oxide = 15-3, Carbonic acid =13-3: total 10000. 



A question of no slight interest in regard to the changes which meteoric 

 irons undergo during their passage through the atmosphere is whether their 

 surface becomes fused. Prom his study of the Tennessee meteorite, Dr. Smith 

 has decided it in the negative. The fact of the delicate reticulated surface 

 having been preserved is a proof that the heat, instead of having been raised 

 to a high temperature on the surface, has quickly been conducted away into 

 the mass of the metal. Had fusion of the superficial layer taken place, the 

 meteorite would have been coated with molten oxide. 



The author finds in this fact a confirmation of his theory that the Ovifak 

 masses are not of meteoric origin. 



1840. — Szalnicza, Arva, Hungary*. 



For his investigation by means of the spectroscope of the gases occluded by 

 meteoric iron, Wright examined those from the Ked Eiver, Texas, and Taze- 

 well Co., Tennessee (which see below). 



The amount of carbon present in the former iron was found on chemical 

 examination to be very small ; in the latter none was detected. A series of 

 experiments were therefore made with the above iron, which, according to 

 Liiwet, contains a larger amount of carbon. While it was an easy task to 

 remove fragments of the above-mentioned irons, great difficulties were ex- 

 perienced in the present case, the metal having nearly the hardness of steel. 

 When the tube containing fragments of this iron was exhausted, and before 

 heat was applied to it, the spectroscope indicated the presence in the " vacuum- 

 tube" of both hydrogen and carbon gases; the lines of the former element 

 were very brilliant, and the first, second, and third bands of the latter, 

 counting from the red end, were visible. The application of a heat hardly 

 suificient to pain the hand caused an entire change in the appearance of the 

 vacuum-tube ; the broad part took a greenish hue, while in the spectroscope 

 the carbon bands shone quite brightly. "Wlien the heat was raised to a tem- 

 perature considerably short of redness, the only change noticed in the spec- 

 trum was a greater intensity of the carbon bands ; the gas collected at this 



* A. W. Wright, Aiuer. Journ. Sc. 1875, ix. p. 294. 

 Amer. Journ. So. [2], vol. vjii. p. 439. 



