90 



THE GEOLOGIST. 



The mass is covered thickly with a series of shallow pits or depres- 

 sions, about i to ^ of an inch deep. The spaces between the holes 

 are bright like steel. Its weight is about 12 or 13 lbs. 



Tn consequence of finding a difficulty in fixing the position or po- 

 sitions of the Atacama Meteorite in 1826,1 gave Peine, Guanaquero, 

 Chala, and two other spots north of Challa, all in the desert of Ata- 

 cama ; also Mino, to the east of Mani, near the Peruvian and Bolivian 

 boundaries. I tried to get across the desert in 1828, from the coast 

 of the Pacific, in the hope of examining the localities of Guanaquero 

 and Peine, near to one or other of which places I hoped to find the 

 meteoric deposit. I was lost for awhile in the desert of Atacama, 

 and had to return to the coast. Near to Toconao, north-east of Peine, 

 was supposed by Sir W. Parish to be the spot ; but in 1853, Dr. 

 Philippi determined ImiJac, a few miles south-west of Peine, to be 

 the spot, or one of the spots of the fall of the Atacama Meteorite. 



A very large specimen from Atacama is in the possession of Domey- 

 ko, in Santiago, in Chile; some others I have seen, as well as many 

 small fragments which fell at Imilac ; as to my small specimen obtained 

 in 182H, when I was in Tarapuca, it may or may not have been col- 

 lected at Imilac* 



The large specimen of the Atacama Meteorite deposited by me in 

 the British Museum, I procured on the west coast in 1854. I have 

 had some doubts as to whether Imilac ought to be given as the locality 

 of its fall. I made this observation in my paper to the Meteorolo- 

 gical Society, 1858, as to this specimen ; the same will apply to a 

 slice of meteoric stone in the same Museum, and that in the Museum 

 of Practical Geology. The information I had was what I let the Bri- 

 tish Museum have, that it (and others, one weighing over 50lbs.) 

 were brought to Cobija by a muleteer, from somewhere to the east 

 in the desert of Atacama, and it was thought there were several 

 similar deposits in the track to Antofogasta." 



These specimens have the external mechanical character of the 

 Imilac specimens, but the metallic part is dark, as if much oxidized, 

 and the earthy part is more crystalline. 



lSico],in his 'Mineralogy,' gives an analysis by Eivero of meteoric 

 iron from " Potosi :"— iron, 90-24 ; nickel,' 9 76 = 100-0. Domeyko 

 gives for tlie Atacama one (Imilac) -—iron, 8S'54 ; nickel, 8-24; 'co- 

 balt, I'll ; silica, 016. Prom this diflference of composition compared 

 with that of the one from " Potosi," we may say that Imilac was not 

 its place of deposit. 



1 advert in my paper to the Meteorological Society to three stones 

 found four leagues inland from Playabrava (23° 35'), two round and 

 porous, the other porous, flat, and triangular. I suspect them to be 

 meteoric (for they are said to be of "'iron"), and the locality they 

 were found in, although near the latitude of Imilac, is much further 

 to llio west. Having disposed of these amygdalo-peridotic varieties, 



* I iiave 23° 30' S., 68'' 50' W. as the position of Dr. Reid's specimens (which are 

 w"^' "'"^ ""^'"^ '^''^'^^ ^^^^ Imihc, which is in 23° 49' S., 



