108 Kansas Academy of science. 



Coextensive with this area of devastation, as far as I have had an opportunity to 

 examine it, and, I presume, coextensive with its entire limits, there is scattered over the 

 country — resting upon the surface or buried under recent alluvial deposits — silicified 

 wood which grew at a time intermediate between the carboniferous vegetation and our 

 recent forests. The carboniferous wood is invariably imbedded in the stratified rocks, 

 while this intermediate wood is invariably upon the surface, or resting under recent 

 alluvial or vegetable deposits. This would indicate that portions of Kansas, at least, 

 were covered with forests at the time this widespread destruction began, and subsequent 

 to the Carboniferous age, portions of which must have been swept away and destroyed 

 by the submergence of the country, while other portions of it, where the conditions 

 were favorable, were silicified in the mineral waters of the seas, and left scattered over 

 the old sea-bed in positions at or near where they are now found, when the land, for the 

 last time, in southeastern Kansas, emerged from the water. 



The petrified remains of this intermediate forest, when its limits are fully known, may 

 give some clue to the time of this era of destruction. To the westward, in the region of 

 middle Kansas, the bones of species of animals now living, and the remains of man, have 

 been found buried under alluvial deposits of wide occurrence and at considerable depths 

 below the surface. If the intermediate fossil wood should be found, as it probably will 

 In-, associated with these buried remains, it will render the probability great that this 

 era of waste was comparatively recent, and that man may have reposed under the shade 

 of the forests which preceded it, and which were involved in its devastations. But there 

 is an equal probability that it may have occurred at an earlier date of the world's his- 

 tory. 



This last era of submersion in Kansas seems to have been one of destruction, for no 

 fossil remains of sea life seem to have been left to indicate the age of occurrence ; and 

 to determine this a resort must be had to preceding life, or synchronous air-breathing 

 animals which may have been carried out by ocean currents and buried under their de- 

 posits. 



The absence of life, or the fossil remains of life, of this era, is not to be wondered at 

 when we consider the widespread destruction which took place in it. All of the time, 

 rocks, which were torn from their beds, were destroyed utterly, either by the chemical 

 action of the acids in the water, or ground up by the attrition caused by waves and cur- 

 rents — or, most probably, by both these causes combined — and carried away, in part, to 

 distant and deeper waters, and in part left to form the soils of the local valleys. The 

 more enduring silica was rounded by the action of the water, and left in the beds so 

 widely distributed over the country. Where the destroyed strata were composed of 

 limestone alone, no pebbles are to be found, but where the lime-rocks contained masses of 

 chert, or where the strata were composed of chert entirely, the pebbles are found, and 

 the beds vary in thickness in proportion to the amount of material torn down. Where 

 the destroyed strata are in a locality of sand-rock, and composed of sand-rock alone, the 

 gravel-beds are composed of their fragments alone. There may have been, and undoubt- 

 edly was, some drifting together of the pebbles, caused by the waves and currents of the 

 sea, but in the main they are confined to the locality where they were torn down, and are 

 nowhere of any considerable thickness. There are now in the museum of the University 

 of Kansas perhaps a hundred specimens of fossil shells, collected from these beds at 

 various and widely-separated localities, identical with the undisturbed fossils of the 

 respective localities where they were found, and which prove conclusively, if additional 

 proof were needed, that the pebbles composing these beds are but the more enduring 

 parts, or silica, entering into the composition of the local rocks destroyed. The silica, 

 being impervious to the acids which aided the destruction of the lime-rocks, remains 

 imbedded where showered down from the general ruin, and as left when the land emerged 



