222 KANSAS ACADEMY OF SCIENCE. 



HEIGHT OF THE ICE. 



This ought to give some clew to the height of the ice at its front. An- 

 other clew is obtained in Martin's Hill, west of Topeka, the hill west of the 

 sugar mill, and the hill at Valencia, all overlooking the Kaw, and none of 

 them covered by the ice, but standing as islands surrounded by fields of ice, 

 since the ice that passed up the valley on either side spread out and met a 

 short distance south of these hills. In Kansas, too, some idea may be had of 

 the total height of the ice in this way: The front of the ice in this state was 

 the arc of a circle, as shown by that terminal boulder train. The focus of the 

 arc is a little above White Cloud, Doniphan county. The main glacier came 

 straight down the Missouri valley, or a little east of it, and spread out to the 

 south and westward like the radiating lines of an hepatic or the venation of a 

 maidenhair fern. It must also have spread to the southeastward, until held 

 in check by vast fields of ice in that direction. 



A field of ice that failed to touch Burnett's mound, though it passed two 

 miles further south on either side, could not have much exceeded the height 

 of the mound, say 1-50 feet. At Martin's hill the ice could not have exceeded 

 400 feet in height, else it could easily have passed over the hill; since it 

 passed over lands of equal height wherever the northern slopes were more 

 gentle. If we assume, then, that the height at Martin's hill, six miles north 

 from the ice front, was 400 feet, and allow an average of 40 feet to the mile 

 as the slope of the surface of the ice, it will indicate 3,000 feet as the height 

 of the ice at White Cloud. The elevation of the uplands at White Cloud is 

 1,000 feet above sea level, the same as at Topeka. The elevation of the 

 highest intervening lands is 1,150 feet. 



SOURCE OF THE ROCKS. 



It has always been a question where these rocks could have come from. 

 We find no rocks just like them in any of the states m-entioned. Hence they 

 are not local rocks. Similar rocks are to be found in situ in Keewatin, north 

 of Lake Winnipeg, in eastern Manitoba, northeastern Minnesota, and in 

 Ontario, north and east of Lake Superior, along v/hat is known as the Lauren- 

 tian range of mountains. 



These stones, Prof. Ulysses S. Grant, of Minneapolis, writes me, are found 

 iii situ nearly all over Minnesota. They are not found this side of Minnesota, 

 except these (Nos. 17 to 22, and 24), which are found in the Sioux quartzite, 

 in the valley of the Big Sioux and farther east. This specimen (No. 20) con- 

 tains evidence of glaciation in itself. Look at these pebbles. Waterworn, 

 are they not? They are worn exactly the same as similar pebbles are worn 

 by ice and water at the present day. Yet immeasurable ages have passed 

 over this earth since the formation of these pebbles. Here is a specimen (No. 

 24) from the same formation that contains evidences of water and no ice. 

 How do you account for those beautiful lines except on the hypothesis that 

 these particles were laid in water in which the currents were regularly re- 

 versed, intermittent, or otherwise changed? This specimen (No. 23), a red 

 jasper, Professor Grant says, "is known to form pebbles in the base of the 

 Sioux quartzite, near New Ulm, Minnesota." He says further: "This is the 

 most probable source for your specimen. Exactly similar rocks are found in 

 the iron ranges on both sides of Lake Superior." 



How came these rocks in our boulder train so far from their native home? 

 The question as to whether they were washed there by ocean waves would 

 be at once decided in the negative. The question as to whether they were 

 transported by icebergs across seas of open water has been considered; and 



