:>04 The American Geologist. St Member, i*94 
\ alley. The loess was deposited apparently long a Hit the earliest sheel 
of the glacial drift, but ii is bordered eastward by n later drift sheel 
with which ii seems to have been contemporaneous. The Columbia 
and loess deposits therefore are thought t<> represenl ;i somewhat late 
stage of the < llacial period. 
Program in tin geological survey ,f tin (in, it lakes. .1. \Y. Spencer. 
The great lakes tributary t<> the St. Lawrence river are ascribed i<> dif- 
ferential movements of subsidence and elevation during the Pleistocene 
period, whereby portions of preglacial river valleys have been trans- 
formed into lake basins. Previous to thai period the upper Ohio, the 
Allegheny, and other riversof northwestern Pennsylvania, Howed north- 
ward to what is now the bed of lake Erie; from tin- southern part of the 
area of lake Michigan a river flowed cast across tin- lower peninsula of 
Michigan to lake Huron: and drainage from the Georgian bay area 
passed eastward to lake Ontario, whose bed was a part of tin- upper 
course of the preglacial St. Lawrence. 
Duration of Niagara falls . .1. W. Spencer. During the earlier and 
longer part of the history of the Niagara ri\er. it is thought to have re- 
ceived .only the outflow of the Erie basin, the three upper lakes mean- 
while outflowing by the way of lake Nipissing and the Ottawa river. 
Computations From the changing conditions of the Laurentian lakes in- 
dicate about 32,000 years as the time which has been occupied in the 
erosion of the gorge below I he falls. 
Drainagt of tin Great lakes into the Mississippi river by way <>f Chicago. 
.1. \Y. Spencer. 
()h standard sizes for trays, drawers, mid cases for mineralogical mid mi- 
croscopical cabinet*. W. <i. Levison and 1). S. Martin. 
A prehistoric relic, with extracts from a survey of lands in Monro* mid 
Ontario counties, X. )'.. which were under the ancient Uikt of Ontario. ('. 
H. Jenner. 
Exhibition <f << microscopt made of aluminum fur portability, mid modi- 
fied in construction /« adapt it for searching over tin surfact fir large min- 
eral specimens. Wallace G. Levison. 
Exhibition of map and photograph of a peat hid in Prospect Park, Brook- 
lyn, X. )'.. imidi in ism . ir/n n tin /nut was removed and tin excavation 
fiUed. Wallace <;. Levison. 
Th, geological atlas folios issued by tin- V. 8. Geological Survey. F. H. 
Newell. 
Tin miii, mis of Paterson, Upper Montdair 1 , and tin Palisades, JV. J. 
Joseph H. Hint. An interesting collection of these minerals was ex- 
hibited by the local committee. 
On the agt oftht st. Clair limestone of Arkansas. S. H. Williams. 
Tin report mi progress in Geology from tin Centennial to tin Columbian 
expositions. Jed. Hotchkish. 
OUand tins in Kansas. Erasmus Baworth. 
Siiihi alteration phases inthi granitic rocks of t/it Northwestern States. C. 
W. Hall. 
San Francisco was chosen as the place of meeting of the 
Association next year, lor which Prof. Edward W. Morley, of 
Cleveland, Ohio, was elected president. The officers of Sec- 
tion E, elected for that meeting, are Maj, Jed. Hotchkiss, of 
Staunton. Va.. vice president, and Prof. J. Perrin Smith, of 
Palo Alto. ( al.. secretary. 
