254 K Cohen — Meteoric Iron from Soudan. 



Art. XXVII. — Meteoric Iron from JV' Goureyma, near 

 Djenne, Province of Mcccina, Soudan;'* by E. Cohen. 

 (With Plates II-IY.j 



The meteorite that fell on June loth, 1900, in Soudan near 

 N'Groureyma 3 north of Koakourou, in the Province of Macina, 

 weighed 37-J kilograms and is roughly of the form of a drop 

 or flat, wedged-shaped mass 57-J cm long, with its greatest width 

 28 cm , about one-third of its length. The wedge tapers towards 

 both ends, the sharpened being 3f cm , and the blunt end 14 cm 

 broad, so that the edges appear to be bulged out. This form 

 as a whole, as well as the various scallopings and jagged pro- 

 jections in detail, will be made clear by reference to Plates II 

 and III. Varying between 1 and 9 cm in thickness, the mass is 

 so thin as to be bounded practically by only two surfaces which 

 meet in a pretty sharp edge (Plate III, fig. 2) : one surface 

 (Plate III, fig. 1) being considerably more convex than the 

 other (Plate II). 



From the characteristics of both surfaces it may be concluded 

 with certainty to be a conspicuously " oriented meteorite," of 

 which the natter side forms the back and the more convex 

 surface the breast. Compared with the breast the back is 

 characterized by shallower, larger, and for the most part 

 elongated depressions, broader and more rounded edges, 

 smoother surfaces, less uneven and somewhat lighter crust, 

 sharper projecting points or tongue-shaped prominences, and 

 coarser drift effect which is confined to the pointed end. The 

 breast has a greater convexity ; smaller, deeper and for the 

 most part rounded cavities, with small bowl-shaped formations 

 on the walls, producing a pock-marked appearance ; darker and 

 rougher crust; finer and more abundant drift effect, which is 

 most sharply defined toward the thicker end; and an isolated, 

 deep cavity on the shield-shaped part. Undoubtedly, during 

 the passage of the meteorite through the air, the broader part 

 was directed forward. This is shown by the projections and 

 jagged prominences directed toward the pointed end, the 

 orientation of the elongated depressions, the overlapping of 

 the crust and nickeliferous iron at the edges, the course of the 

 general drift effect and the nature of the abrasion ; supposing, as 

 I imagine, that this occurred within the atmosphere by air erosion. 



The original form may, however, have been much more 

 regular than the present one and may, perhaps, be compared 

 to a flat oval shield whose apex is eccentric and lies near the 

 highest point of the still remaining bulge. The position of 

 the only deep cavity on the bulge has a like significance. It is 



* This meteoric iron is now in the hands of H. Minod, Comptoir Mineral- 

 ogique et Geologique, 3 Cours des Bastions, Geneva. 



