710 
Triply Asymptotic Systems of Surfaces,’ by Dr. 
L. P. Hisenhart; ‘Note on Hamilton’s Deter- 
mination of Irrational Numbers,’ by Dr. H. E. 
Hawkes; ‘Review of Muth’s Elementar- 
theiler,’ by Mr. T. J. I’A. Bromwich ; ‘ Shorter 
Notices’ : ‘ Fricke’s Lectures on Higher Mathe- 
matics,’ and ‘ Béger’s Plane Geometry of Posi- 
tion,’ by Professor H. 8. White; ‘Notes’; 
‘New Publications.’ 
SOCIETIES AND ACADEMIES. 
SECTION OF GEOLOGY AND MINERALOGY OF THE 
NEW YORK ACADEMY OF SCIENCES. 
AT the meeting of the Section on March 18th, 
the following program was presented : 
“The Cambro-Ordovician Outlier at Wells- 
town, Hamilton County, New York.’ In intro- 
ducing the subject of the paper Professor Kemp 
gave a brief account of the physiographic prob- 
lems presented in the Adirondacks and of the 
significance of the smaller outlines of Paleozoic 
strata which occur within the crystalline area. 
He then discussed the Wellstown exposure and 
described it in much the same way as he has 
already done in print in the ‘ Kighteenth Annual 
Report of the State Geologist of New York,’ 
page 145. The general conclusion favored the 
existence of land areas of ancient crystalline 
rocks in the vicinity of Wells, and, it seemed 
to the speaker, that the peculiar sediments 
could not be explained in any other way. 
Pebbles, as large as one’s fist, of gneiss similar 
to that found in the ancient hills, are imbedded 
in the Trenton limestone, and much sand is 
found in the limestones of both the Calciferous 
and the Trenton. It was admitted that the 
present valley is due to faulting, as has been 
previously claimed by Dr. R. Ruedemann, but 
the shores of the late Cambrian and early Or- 
doyician could not have been far from the pres- 
ent outcrops of the Paleozoics at Wells. Mr. 
Van Ingen and Doctors Levison, Dodge, White 
and Julien took part in the discussion of the 
paper. 
Dr. Julien remarked, in regard to the sand 
found in the limestones to which Professor 
Kemp referred, that although the smaller and 
angular portion of the sand, in which feldspar 
is common, and particles of garnet, epidote 
SCIENCE. 
(N.S. Von. XIII. No. 331. 
and menaccanite also occur, may possibly be 
residual, derived from decay of gneiss adjacent 
to the shores of the ancient basin, the predomi- 
nant quartz grains, well rounded and even per- 
fectly spherical, could not possibly be of that 
origin. Their sculpture indicates prolonged 
action during ages before they assumed spher- 
ical form, and that although found in sediments 
loose or consolidated in all periods from the 
quartzites of the Laurentian down to the pres- 
ent beaches along rivers, lakes and ocean, they 
represent in all cases ancient materials which 
have been worked up over and over again from 
period to period. Inthe Potsdam of the North 
American continent they have been accumu- 
lated in an extensive outer-beach deposit, the 
result of an enormous resorting of materials 
throughout the vast Cambrian time. These 
‘paleospheres’ were doubtless derived from 
the same Potsdam horizon which has yielded 
the oolitic quartz sand of the ‘singing beach’ 
on the shores of Lake Champlain, near Platts- 
burg, not many miles from the Wellstown 
Ordovician outcrop. They certainly were not 
swept into this limestone basin by currents, 
since the absence of sorting and the parallel 
deposition of their axes show that they were 
dropped down from the surface in a continuous 
gentle shower. The conditions which favored 
this consist of the floating of sand from the 
beaches along sheltered bays, such as Long 
Island sound, on every quietly rising tide, 
with its seaward transport, often to hundreds 
of miles off the coast, commonly caught in the 
dredges of surveying steamers, as noted by 
Verrill and others, and in its constant subsi- 
dence over the bottom. Such sand transport 
was plainly in progress over the quiet embay- 
ment occupied by this limestone, from sur- 
rounding beaches supplied from the decay and 
disintegration of an ancient shore of Potsdam 
and Calciferous sandstones. The various sands 
referred to in these remarks were illustrated by 
photomicrographs. 
‘A Method of facilitating Photography of 
Fossils’ was described by Mr. Gilbert Van In- 
gen. The process consists in forming, on the 
surface of the specimen to be photographed, a 
thin coating of ammonium chloride by the com- 
bination near that surface of ammonia gas and 
