520 REVIEWS 
of the drift with many close, but distinctly drawn, discriminations. The 
following Pleistocene formations are recognized : anteglacial silts, pre- 
Kansan, Aftonian, Kansan and Illinoian. The anteglacial silt isa new 
division. Itis explained as having been formed by water and wind ahead 
of the invading pre-Kansan ice-sheet. If that be its origin, it might 
properly belong with the pre-Kansan drift and the division would appear 
unnecessary. If every aqueous deposit of the drift should receive a 
special name, the clarifying effects of analysis would soon be lost in 
confusion. ‘The economic products of Muscatine county include coal, 
though in unprofitable amount, small quantities of gas, building 
stones and clay. 
The geology of Scott county, by Professor W. H. Norton, contains 
much fresh information. ‘The passages in the paper dealing with the 
history of the drainage and with the stratigraphy are of special value. 
Touching the former, this region is particularly interesting because of 
its location at the southern limits of the driftless area and the con- 
sequent complexity of the drift phenomena arising from the mutual 
interference of the ice lobes at this place. 
The report on the artesian wells of the Belle Plaine area by H.R. 
Mosnat gives a thorough exposition of the geology of the water-bearing 
formation, the amount of the flow and the source of the water. ‘The 
computations rising from the study of flow and supply develop many 
facts which simplify to a great degree the conception of the combina. 
tion of conditions appropriate to the formation of artesian wells. A 
most significant passage is that discussing the rate of movement of the 
underground water through materials of different texture. It is 
estimated that nineteen years would be required for the water of the 
aquifer to move in a direct line from Vining to Ladora along the major 
axis of the artesian area. Hence, the writer concludes, the great exhaus- 
tion of the water body brought about at Vining by the remarkable flow of 
the great Jumbo well when it was opened, will not affect the flow at 
Ladora before the year 1905. He also shows the limited extent of sur- 
face actually necessary to supply the water for the aquifer and the ade- 
quacy of the rainfall to produce the supply without any recourse to the 
extravagant superstitions which have made this artesian area ‘the 
eighth wonder of the world” in the minds of the inhabitants of the 
region. ‘The discussion is closed with a paragraph on the uses of the 
water, which largely relegates the wells to the category of interesting 
