362 J. D. Dana—Flood of the Connecticut River Valley. 
age-area at any given time would have been 965 cubic miles, 
making the total about 8,215 cubic miles. 
3.) Sources of the Water.— Melted ice and unfrozen waters 
from the precipitation over the drainage-area were the sources 
supplying the flooded streams. 
he precipitation, to produce the snows needed for the Glacial 
era, must have been large, much larger than now. e amount 
at the present time for the part of the drainage-area north of 
Massachusetts averages 42 inches a year, and for the part south, 
46 inches; while on Mt. Washington, just east of the area, the 
annual fall is between 55 and 80 inches. In 1873, 78°56 inches 
were registered on Mt. Washington. 
n the Glacial era the conditions must have occasioned still 
he relations were consequently like those between the tropi- 
cal Indian Ocean and the seaward mountain ridges of India, 
though less extreme. In India, at many localities, the mean, 
annual rain-fall is 100 to 160 inches, while at three stations on 
the Ghats, in Bombay, it is over 250 inches, and at one m 
Assam, nearly 500 inches. In such facts we have seemingly 
sufficient reason for estimating the average annual rain-fall of 
the Connecticut valley during the Glacial era to have been at 
least as high as 120 inches. The present high average on the 
isolated White Mountains is good evidence that.90 inches would 
be too small an estimate, and the more so since during the four 
months in which half of the precipitation there takes place, June, 
July, August and September, the slopes are, with small excep- 
tions, free from snow—Mr. Schott’s tables (page 56) making the 
mean for the four years of observations 67°12 inches, and for the 
New England, over which would have blown moisture-ladened 
winds from the region of the great Mediterranean sea of the con- 
tinent; though possibly, owing to the distance from that sea 
and the position of the Appalachians, the annual precipitation 
