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this way. The fire generally occurs through the carelessness of persons who are camping out. The waste of valuable timber is thus erroneous.

As we passed? over the Prairie the unclear becomes unclear that fire is the sole cause of the absence of trees. The Prairie was once covered with trees, because when fire is kept off by cultivations, & the earth loosened by the plough, so as to admit light & air to a greater depth than before, young trees at once appear. Of course the parent trees must at some time or other have grown on the spot. unclear the seeds that were sufficiently near the undisturbed surface to germinate, had germinated, & the young plants that issued from them had been destroyed by fire. Those seeds which chance had buried more deeply waited for the aid of man to give proof of their presence in the soil.

Again both forest & fruit trees when planted by the hand of man thrive well on the Prairie, if only fire be kept from them.

And wherever in the Prairie, as on the rocky faces of Bluffs, or the banks of streams, fire cannot reach, on account of the absence of sufficient grass & undergrowth to convey it, trees, as pines, oaks, willows & poplar abound. The great accumulations of black vegetable mould are to be accounted for in the same way: they are formed out of the burnt & half burnt vegetable matter left by the annual fires of no one can tell how long a period. In the Valley of the Platte this vegetable mould appears to have been carried away by the