Mr. J. S. Cotton informs me that in the vicinity of Mr. Turner's home, Section 6, Town north 18, Range 40 east, on Rock Creek, about six miles below Rock Lake, and in the vicinity of the graves described on p. 140 and the so-called fort mentioned on p. 82, there is a long line of stones running from Rock Creek in a southeasterly direction across the coule to a small draw on the other side. This chain of rocks is about five miles long. The stones have evidently sunk into the ground and show signs of having been there a long time. They have been in the same condition since about 1874 when first seen by the whites, even the oldest Indians claiming to know nothing about them. According to Lewis, game was surrounded and driven in by a large number of hunters or was run down by horses, in the great area of which this is part.[67] It seems altogether probable that a line of stone heaps may have been made to serve either as a line of scarecrows, possibly to support flags or similar objects, which would have the effect of a fence to direct the flight of the game or as a guide to enable the hunters to drive the game towards a precipice where it would be killed, or a corral where it would be impounded. [67] Lewis, p. 182; Ross, (a), p. 316; De Smet III, p. 1026; Lewis and Clark, IV, p. 371. _Notched Sinkers._ Sinkers for fish nets or lines were made of disk-shaped river pebbles. A pebble and the different types of sinkers are shown in Fig. 13. These were numerous on the surface of the beach of the Columbia River near the head of Priest Rapids. They have two or four notches chipped from each side in the edges. When there are two, the notches are usually at each end; when there are four, they are at the end and side edges. Sometimes, the notches are so crudely made that the edge of the pebble is simply roughened so that a string tied about it at this place would hold. One of these sinkers from Priest Rapids was seen in Mr. Mires' collection.