The tons of drying salmon impressed members of the Lewis and Clark expedition as they headed down the river in October of 1805. They were probably the first white men to see the falls, although American and British ships had been calling at the Columbia's mouth since 1792 and their trade goods (and venereal disease) had worked their way up to Celilo and beyond. Celilo custom called for providing visiting tribes with the salmon they needed, but the expedition wasn't tribal and the Celilos were no fools. "They ask high prices for what the Sell and Say that the white people give great prices &c for everything," William Clark grumbled in his journal in November of 1805. Thus, perhaps, a tourist industry was hatched. Clark described the falls and adjacent rapids that tumbled through several miles of basalt formations as "foaming and boiling in a most horriable manner." Beginning in the 1830s, gold seekers and early settlers forced the tribes out of the river valleys leading to the Columbia, and the tribes found a welcome among the Celilo on the Columbia. Treaties of 1855 then herded the Indians onto reservations after they signed away huge tracts of traditional lands and other wealth. Some stayed on the river, but all members of the river tribes kept their fishing rights to the "usual and accustomed" places, and the falls remained known as "an Indian place." But access to the "usual and accustomed" fishing areas, guaranteed by treaty but not well defined, often was blocked by whites who had taken over land. And murderously efficient fishing methods by non-Indian fishermen (such as fish traps and fish wheels, since outlawed) fed the voracious downriver salmon canneries. Pollution and destruction of spawning grounds also played a role in reducing the salmon runs to a trickle of their historic highs. But dams were a major factor. At the height, as many as 16 million salmon passed through the river. By 2006, only about 1 million adult salmon and steelhead heading upriver to spawn were counted at Bonneville Dam, the first of 14 dams on the Columbia. Incoming and Outgoing messages protected by Trend Micro PC-cillin program