126 Field Columbian Museum — Geology, Vol. III. 



the meteorite was obtained by Jackson, was at that time located along 

 Ponca Creek in Nebraska. It seems reasonable to suppose that the 

 meteorite was found in the vicinity of this creek, and the name Ponca 

 Creek has the additional advantage of containing that of the tribe by 

 some member of which the meteorite was probably originally found. 

 For the meaningless name Dakota, therefore, that of Ponca Creek 

 may well, in the opinion of the writer, be substituted. 



SALINE. 



Some further observations may here be added to the brief account 

 of this meteorite given by the writer in 1902.* The approximate 

 place of find of the meteorite was kindly indicated to the writer by Mr. 

 S. A. Sutton, and this is shown in Plate XLI. No other observations 

 of the fall than those already made by Mr. Sutton and reported by v the 

 writer seem to be known. The shape of the meteorite may be de- 

 scribed as approximately that of a truncated, four-sided pyramid. 

 The base of the pyramid, shown in Plate XL 1 1, was plainly the rear side 

 of the meteorite in falling. It is the broadest surface of the mass, and 

 has an area of about 144 square inches (900 sq. cm.). In outline it is 

 roughly circular. Mr. Sutton states that this was the surface on which 

 the meteorite rested when found, but this position could have been 

 brought about by an overturn when striking. It was more heavily 

 coated with carbonate of lime when received at the Museum than any 

 of the other surfaces. It is nearly flat, though slightly concave, and 

 shows the broad, shallow pits characteristic of these surfaces of meteor- 

 ites. On the opposite side of the meteorite a surface having the form 

 of a long and narrow isosceles triangle runs nearly parallel to it and 

 the thickness of the meteorite between the two surfaces ranges from 

 7 to 8 inches (18 to 20 centimeters). From the parallel surface the 

 meteorite slopes away at angles of 40 , 50 , 6o° and 90 approximately. 

 Three of these surfaces are approximately plane, the others are 

 rounded. A view of the meteorite showing this feature is given in 

 Plate XLI I. Views of the mass from two other sides were published 

 in the Catalogue of Meteorites of the Museum. f The plane surfaces 

 show practically no pits, the others are more or less irregularly pitted. 

 The more symmetrical of these pits are oval in form, from yi to ^ 

 inches in their longest diameter and have a depth about one-fourth as 

 great. All the edges produced by the meeting of different surfaces of 

 the meteorite are rounded. 



* Science, N. S. Vol. XVI, pp. 67, 68. 



t Pubs. Field Col. Mus. 1903, Geol. ser. Vol. II, Plate XXX. 



