130 



REPORT 1879. 



both magnetic pyrites and nickel-iron have a distinct concentric arrange- 

 ment. 



The stone of Tieschitz belongs to that division of the chondritic 

 meteorites which Tschermak some years since classified as remarkable for 

 ' many brown finely fibrous chondra.' The specific gravity of the stone 

 is 3'59. It contains about 85 - per cent, of non-metallic minerals. No 

 trace of any mineral resembling a felspar could be detected. The 

 percentage composition of the stone was as follows : — 



or. 



Olivine . 



Bronzite and enstatite 



Augite . 



Magnetic pyrites . 



Nickel-iron 



38-79 



33-84 



1401 



4-08 



9-28 



10000 



Meteorite-fall at Esterville, Emmet County, Iowa, May 10, 1879, 5 p.m. 1 



A meteor exploded over this spot and was seen to fall in full daylight. 

 One fragment weighing 500 lbs. fell on railroad land and was dug up 

 from a depth of 14£ feet in a stiff clay soil. Another portion weighing 

 170 lbs. fell at a distance two miles from the first. Many smaller 

 pieces, of a few ounces or pounds weight, were scattered in the vicinity. 

 The smaller mass fell upon a dry knoll and penetrated the earth verti- 

 cally to a depth of 4^ feet. The fall was accompanied by a noise 

 described as a continuous roll of thunder accompanied by a crackling 

 sound. The stone has been placed in the hands of Professor C. W. Hall, 

 of the Minneapolis University, for complete examination. The pre- 

 liminaiy examination points to the metallic portion consisting of an 

 alloy of iron, nickel, and tin. Full half the mass consists of stony 

 matter, which appears in dark-green crystalline masses imbedded in a 

 light-grey matrix. When the whole" is powdered a violent reaction 

 ensues on the addition of hydrochloric acid, which is increased on boiling. 

 The boiling acid appears to dissolve all but the grey matrix. Some of 

 the crystalline masses are two inches in thickness and exhibit distinct 

 monoclinic cleavage. Under the microscope, in thin sections, olivine 

 and a triclinic felspar appear to be imbedded in a matrix of pyroxene. A 



1 Amer. Jour. Sc, vol. xviii., p. 77. 



