218 Scientific Intelligence. 
fell. But did this waste ordinarily amount on the northern border 
be confined : the other two suppositions. If observations in the 
Arctic shall furnish something definite as to the probable loss by 
evaporation, this would still further diminish the doubts 
may be that the diminution in the rate of precipitation, conse- 
quent on the extension of the glacier southward (on the principle 
mentioned on page 206) was the — means in fixing an ultimate 
limit to the thickness of the glac 
ains of boulders, oe on the transport of oS to 
a level above that of their source ; by Dr. SrEPHEN C 
municated.)—lI have called attention frequently, in varictin ways, 
to trains of boulders extending from a hill in Canaan, Columbia 
o., N. Y., across Richmond, Lenox and Lee, Mass.* Two of these 
iy so. 
have ticen often visited by geologists, and several theories 
rare Ae shed. I have been aware, for several ro that a train some 
two miles south of these was well marked for half a mile on the 
east side of the hill—locally called Dean’s Tall betweat Canaan 
and Richmond; but a oe tiie time to trace it to its source 
was not found until the last seaso 
Lea 
. 
‘es 
eighty rods, without seeing a specimen, then found another line of 
blocks. I followed this into the woods and soon found another 
sopping © rock was in sight. The boulders extended, as ; far as the 
permit me to see, east and west. Following my 
ries ee yaieiebls guides, I went west nearly to the top of the hill 
before any rock, in place, appeared. At last I stood on the bare 
ledge—the objec ct of my puree Although I had no doubts of » 
success from the first, yet it was not without emotion that I 
followed, by the aes aig! left behind, the path of these 
alge allay the valley and up the long ascent of the eastern 
hill, until they mingled with my old acquaintances on its cmmrai 
* An CaS it of these trains of boulders, as observed by Dr. Reed, 
in Hitchcock’s Geological Repo rt of Massachusetts, and the latest ettalte Ane . 
tiquity of Man, chapter xvi 
