Note 169 — {122} CHAPTER VII

This velocity of current is equalled by that of the Cassiquiare in South America, and probably surpassed by the Oronoko, the average descent of whose bed is thirteen inches to the mile of 950 toises (6 feet 4.376 inches per toise). See Humb. Pers. Nar. vol. v. p. 637, and vol. iv. p. 452. La Condamine and Major Rennel suppose the mean descent of the Amazon and the Ganges, scarce four or five inches to the mile, which is about equal to that of the Mississippi, according to the most satisfactory estimates we have been able to make.—James.