Erosion in the Basin of the Arkansas River 



335 



MATERTAI, CARRIED BY THE ARKANSAS RIVER PAST UTTLE ROCK 

 DURING THE YEAR 1887-8. 



The total bulk of this material would make a cube whose 

 sides would be 749.2 feet in length.* The total suspended 



*The specific gravity of the suspended matter is assumed to be 2.13 — 

 an assumption based upon an average of seven determinations of the 

 specific gravity of Arkansas River sediments. It is worthy of note that 

 six of the samples used in these determinations were taken from sedi- 

 ments deposited naturally along the river, and one of them was taken 

 from the water used in making the laboratory determinations on sedi- 

 ments. The specific gravity here used is therefore somewhat too high. 



DETERMINATIONS OF SPECIFIC GRAVITY OF ARKANSAS RIVER SEDI- 

 MENTS. 



No. I. — Sp. gr. 1. 7921. Collected Nov. 13, 1888, about 40 feet east of 

 the St. Louis, Iron Mountain, and Southern Railway bridge (upper 

 bridge) on the north bank of the river within a few feet of the water's 

 edge. 



No. 2. — Sp. gr. 1.7764. Collected Nov. 13, 1888, about 100 feet east 

 of the St. Louis, Iron Mountain, and Southern Railway bridge on the 

 north bank of the river. 



No. 3. — Sp.gr. 1.8043. Collected Nov. 13, 1888, about 40 feet west of 

 the St. Louis, Iron Mountain, and Southern Railway bridge, on the 

 north bank of the river. 



No. 4. — Sp. gr. 1. 8014. Collected Nov. 13, 188S, about 100 feet west 



