Читать книгу Journal of Travels From St. Josephs to Oregon онлайн

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The traveler soon after leaving St. Josephs, westward sees prairie in all stages of formation, from the dense forest to an entire prairie. This, with the dense forests of young timber eastward, where the white man has forbidden the practice of firing prairies, seems to be a convincing proof of the aforementioned mode of prairie formation.

It has been noticed in the State of Illinois, and some other places, where the plowman is permitted to glide his plow smoothly over the beautiful landscape, that there is an exceedingly fine scouring material lying near the surface of the soil, so that steel mold boards, on a very short use of them, are seen to present a polishd surface, on drawing them from the soil.—Ages of constant burning of the prairie grasses must necessarily produce a great amount of very fine coal dust and ashes, which, by the beating rains from year to year, would cause it to mingle with the earth to the depth of several inches. Such is the probable cause of the scouring material of these plains.