See quotations.
1845. There are some low ravines, (in the country called slues,) which are filled with water during freshets, and at these points the bottoms are overflowed.Joel Palmer, Journal, p. 99 (Cincinnati, 1847). (Italics in the original.)
1846. [The rivers empty into the Bay] by numerous mouths, or sloughs as they are here called. These sloughs wind through an immense timbered swamp, and constitute a terraqueous labyrinth of such intricacy, that unskilful and inexperienced navigators have been lost for many days in it, and some, I have been told, have perished, never finding their way out.E. Bryant, What I saw in California, p. 343 (N.Y.).
1846. It was right good luck, said he as he drove off, that we didnt get slued [caught in a freshet] afore we got to town.E. W. Farnham, Life in Prairie Land, p. 49. (Italics in the original.)
1846. I massy, you cant do it,the road is so wet, and the slues so full of water. Theres a slue right out here that you couldnt get across at all, so youll have to wait.Id., p. 52.
1849. Now commenced the tedious and laborious operation of warping through the slough, rendered necessary by the strength of a current like a mill-race.Theodore T. Johnson, Sights in the Gold Region, p. 136 (N.Y.). (Italics in the original.)
1850. A few miles further on, we came to what is termed a slough, or lateral branch [of the river].James L. Tyson, Diary in California, p. 54 (N.Y.).