We have now ended our connection with the Council and bid adieu to our Indian friends. It is therefore an appropriate place to say, that we subsequently discovered we had been all the while unconsciously treading on a mine. Some of the friendly Indians afterwards disclosed to the traders, that during the whole meeting of the Council, active negotiations were on foot to cut off the whites. This plot originated with the Cayuses, in their indignation at the prospect of being deprived of their lands. Their programme was, first to massacre the escort, which could easily have been done. Fifty soldiers against three thousand Indian warriors, out on the open plain, made rather too great odds. We should have had time, like Lieutenant Grattan[2] at Fort Laramie, last season, to have delivered one fire and then the contest would have been over. Their next move was, to surprise the post at the Dalles, which they could also easily have done, as most of the troops were withdrawn, and the Indians in the neighborhood had recently united with them. This would have been the beginning of their war of extermination upon the settlers. The only thing which prevented the execution of this scheme was, the refusal of the Nez Percés to accede to it, and as they were more powerful than the others united, it was impossible to make this outbreak without their concurrence. Constant negotiations were going on between the tribes, but without effect, nor was it discovered by the whites until after the Council had separated. Footnote 2: Brevet Second Lieutenant John Lawrence Grattan, Sixth Infantry, was killed, with all his party, by the Sioux Indians, in what is known as the "Grattan Massacre," near Fort Laramie, Neb., August 19, 1854.—ED. ------------------------------------------------------------------------ _Tuesday, June 12th._—We were up bright and early this morning, expecting by sunrise to have been on our march. But some of the horses had strayed away during the night and it was eight o'clock before they could be all collected to enable us to set out. After riding thirty miles we reached the Umatilla. Here we found a sergeant of the 4th Infantry and five men encamped, who had been sent to meet us with provisions. Just then a pouring rain began, and we were glad to make our preparations for the night.