THE ARISPE METEORITE. 83 



during a visit of Mr. Wuensch to that vicinity, and this expert 

 promptly recognizing it as a genuine meteorite, he secured it and had 

 it transported to his Denver home. From this owner the meteorite 

 has, at last, come into my hands to be cut, studied and disposed of, 

 he reserving a slice for the mineral collection of the Colorado Scientific 

 Society. 



The specimen, as it came to me, had nothing of remarkable 

 interest in its exterior. It is as irregular and shapeless as are nearly 

 all masses of meteoric iron, notably those from Mexico and our 

 southwestern states, where prolonged decomposition has with most of 

 them corroded and broken down the sharper angles. A view from 

 one side shows a parallelogram about 16 inches long by 12 inches at 

 one end and about 9 inches at the other. This surface shows no true 

 pittings, but a few shallow concavities, one of them nearly an inch 

 across, due to the deep decomposition which has ensued, doubtless, 

 since its fall. On the opposite side the form is more trifid, as shown 

 in plate IX, and measures 18 inches in greatest length, 133^ inches in 

 greatest breadth, and 13 inches in thickness. Its surface is covered 

 with evenly distributed shallow pittings, ranging from i ^ to 3 or 4 

 cm. in diameter. These are sharp in outline, this surface having been 

 less worn or decomposed since the fall than have been the other sides 

 of the mass. On one side is a large depression, nearly 3 inches in 

 depth and in greatest width, semilunar in shape and with nearly 

 vertical walls on two of its sides. This deep pit-like valley has on 

 its bottom and sides, smooth surfaces, without either ridges or pittings, 

 which give strong indication of the fact of the present vacancy having 

 once been filled with matter which has been worn away or decomposed 

 and fallen out, probably a great troilite nodule. This empty cavity is 

 indeed the most striking feature of the outside of the mass. 



On a section of the iron (Plate X) troilite nodules are quite 

 abundant, some of them up to 30 mm. in diameter. In several 

 instances within these nodules are small patches and angular fragments 

 of the nickeliferous iron. (Plate XI Fig. 2.) These nodules are 

 surrounded with an envellope of schreibersite. In two or three of the 

 nodules were found masses of chromite from 4 to 5 mm. in diameter, 

 and in one instance on the edge of one of the plates was chromite 

 nodule 12 to 14 mm. in diameter. On some of the surfaces that 

 have been polished or etched there have occured in groups of crystals 

 in arborescent form some 10 x 18 mm. in diameter, what is appar- 

 ently cohenite, the carbide of iron. Nothing is more striking in the 



