TIIKEE NEW CHILIAN METEORITES. ■ 227 



differs from pallasites of the Imilac and the Krasnojarsk t^roup, 

 where the cells have almost uniformly rounded walls, conformed 

 to the rounded, instead of angular olivine crystals. The ohvine 

 in Ilimaes is a bright, clear yellow and greenish yellow color, in 

 crystals which vary from small grains to pieces from 5 to 10, and 

 even 15 mm. across. Sometimes these are bunched together in 

 areas from 3 to 5 cm. in either diameter, with no intervening iron. 

 In Plate 20 one of the patches of olivine is visible on the surface 

 at left hand of the upper mass ; and two of them show in the lower 

 mass. 



Plate 24 presents a slice of Imilac below a slice of Ilimaes, 

 showing well the different cell-structure of the two pallasites. 



By careful separation of the olivine from the iron particles 

 in 200 grams of the matter, as it fell from the machine in the cut- 

 ting, we found the former to be 70 grams and the latter 130 

 grams ; a ratio of 54 per cent, of the olivine to the iron. In vol- 

 ume there are 10 parts of olivine to 8 per cent, of iron, assuming 

 specific gravity of the mass as '].'] and that of the olivine as 3.4. 

 In the Ilimaes the coarse structure of the olivine crystals makes 

 great contrast with the almost flour-like grain of much of either 

 niember of the Imilac group, Imilac or Marjalahti. In the latter 

 of these, in all the peripheral portion of the mass, it is so uniformly 

 fine that it has the semblance of having been crowded into the 

 cells as a powder. Borgstrom ventures the surmise that the crys- 

 taline olivine has been brought to this mealy state by the sudden 

 shock received by the heavy mass as this meteorite struck the 

 rock on which it fell. We are pleased to interrupt our brief 

 description of Ilimaes by giving in full a letter, at this moment 

 received from Dr. Aristid Brezina, of Vienna, to whom we, some 

 weeks ago, had sent a small slice of the iron. Dr. Brezina writes : 



" The section weighing 127 grams of a pallasite labeled Ilimaes which you 

 sent me is at hand. It shows the following microscopic and macroscopic par- 

 ticularities. 



"The olivines of brown color measure usually from 3 to 17 mm. in length 

 and 2 to 13 mm. in breadth ; rarely they appear as small particles of 0.5 to 2 mm. 

 in diameter. They show in general polyhedral edges ; very rarely they have 

 rounded edges, which occurs in the smallest individuals only. Schreibersite 

 occurs abundantly, and in three forms ( respective ages) a, individuals of 1-4 

 mm. following immediately after the olivine ; b, small veins between the grains 

 of wrapping kamacite, and c, microscopic grains and crystals in kamacite near 



