180 J. D. Dana—The Flood of the Connecticut River Valley 
the river and its vicinity on a scale of 18 miles to the inch (or 
14 miles to the line), which extends from the village of Co- 
lumbia, toward its source (about 28 miles from the more 
southern of its head lakes called Connecticut Lake) to Long 
Island Sound. The position of the western outliers of the 
hite Mountains is seen to the east of Wells River and 
Haverhill. The Green Mountains, on the west, are too distant 
to be included. The section of the flooded stream just referred 
to is on the same scale as to length measured along the valley 
(not the river) but extends only to Stratford Hollow, 45 miles 
from Connecticut Lake, on account of the northeastward bend 
in the more northern part of the valley. The vertical scale of 
the section is 300 feet to the inch, or 25 feet to the line. In 
this section the longitudinal line AS indicates mean-tide level ; 
BS the level above mean-tide of modern low water in the Con- 
necticut, the figures under the line giving the same in feet for 
the places mentioned below; an ’ flood-level when the 
flood was at or near its maximum-height. The figures directly 
below CS’ give the height of the surface above mean tide at 
_each of the places stated, and those reading vertically, the dif- 
ference between modern low-water level and the highest flood- 
level. 
For the part of the section north of the Massachusetts line the 
levels for mean tide, low water, and maximum flood have been 
few other points I have depended on my own examinations. 
Some of these divergences I here mention in order that the nature 
of the changes introduced may be understood.* 
The height of the “highest normal terrace” at Lancaster, ac- 
cording to Mr. Upham, is 30 feet above low water in the river. 
* In the measurements of the heights of terraces I have used a hand-level. As 
the method is less exact than that employed by Mr. Upham, I have always in any 
remeasurements accept r. Upham’s results. : 
speaking of a terrace, I often use the term terrace-plain for the plain that 
_ makes the top of the terrace, and terrace-front, for the front slope of the terrace, 
the angle of which is often 40° to 42°. 
