Ossawotamie, Kansas, Feb. 17th, 1862.

Here I am on the battle-ground of old John Brown. The thaw setting in, on Monday we commenced forced marches, in order to cross the Osage river before the freshet would affect a rise in the water, but did not succeed, although I, with the right wing, (five companies) crossed on the ice. Must of our baggage and the whole train is yet on the other side, with all the provisions and stores. The ice is now gone, and the river risen 7 feet, so fording will be impossible for days to come. A communication, by canoe only has been established between our troops. We have had to cross several creeks—some on the ice and some by wading.

Although we should have reached Fort Scott on the 15th, we are yet 50 miles from it, and are hemmed in by the tributaries of the Osage, aa 1 encamped in a heavy piece of black walnut, hickory, and other timber,—Fires are, therefore, plenty, and big enough to roast an ox.

Major Russell, of Osage, ten miles below Humboldt, arrived here on Monday night. He gives the most distressing accounts of affairs on our South-eastern border. He and his family have been driven from their home by rebels. A party of Secessionists, said to number 437, are now in Allen and Woodson counties, overrunning those counties and threatening to sweep thro’ the whole Neosho Valley. Major Russell fears that our next news will be that Iola and Leroy have followed the fate of luckless Humboldt. Citizens are leaving that portion of the State in the greatest haste, leaving all their furniture and goods behind. Scouts from Leroy report a force of 1,200 Missourians within thirty miles of Humboldt with the avowed purpose of making a raid upon Kansas.