676 HISTORY AND METHODS OF THE FISHERIES. 
first day of April, 1877, the Penobscot stood 7.25 feet above the dam at Bangor; through April it 
ranged from 7.25.to 4.75 feet ; through May from 4.8 feet to 1.9 feet; through June from 1.9 to 1.4 feet; 
through July from 1.5 to .08; and in August it stood for a few days at the minimum of one-half 
foot. On the 29th of the following November it had risen to 6.25 feet; in December it fell from 5.9 
to 1.5 feet; but through the whole of the following February (1878) it stood at 6 and 7 inches (.5 
aad .6 foot). The highest stage for the spring of 1878 (6.46 feet) was attained in April; the lowest 
stage for the summer was 15 feet, in August; the lowest for the year was 6 inches, Octobér 1 
(with flush boards on the dam); and the highest for the year was 9.2 feet, December 14. In 1879 
the maximum (8.85 feet) was attained May 3, and during that month the water averaged higher 
than in April; it was low (15 inches) July 17, and still lower (1.3 inches) October 19. In 1880 the 
highest water was in May and the lowest between August 17 and October 24, during all of which 
time an extreme drought prevailed, the water standing just at the crest of the dam or an inch or 
two above or below it. Thus in four years we have seen the water at its highest stages twice in 
April, once in May, and once in December, and the lowest stages once in February and October 
(the same year), once in October alone, once in August alone, and once extending from August to 
October. The data existing on the subject are scanty, and the best generalization to be made must 
be founded partly on gencral observation, and would be as follows: The Penobscot is at its high- 
est stages generally, but not invariably, in April or May; it is fairly full from March to July, 
inclusive, and never experiences a drought during those months. The lowest stages occur in 
August and September, often extending into October. In the winter there is generally a depres- 
sion, which in some instances reaches the stage of a drought. The discharge of the Penobscot has 
been estimated by an expert* at 117,000 cubic feet per minute in a severe summer drought, and at 
5,760,000 cubic feet per minute in a heavy freshet. 
WATER TEMPERATURE.—Ice from 15 to 24 inches thick covers all the fresh water during the 
winter. On the lakes it forms about November 15 or 20, and melts out in April, commonly near 
the close of the month, in the southern part of the State. In the more northerly or elevated lakes 
it does not melt until May 10 or 15. The larger rivers, the Kennebec and Penobscot, are closed to 
navigation (at the ports of Gardner and Bangor, respectively) about four months or four and a half. 
The melting of the snow in the spring produces a flood which clears the rivers of ice in April two 
or three weeks before the melting of the lake ice. 
During the winter the temperature of the rivers is generally within one degree of the freezing 
point, but after the breaking up of the ice it rises rapidly, and through the summer generally 
ranges from 60° to 70° or higher, in those parts above the influence of the sea. 
TIDAL PARTS OF RIVERS.—The tidal portions of the Maine rivers are for the most part of 
considerable extent. In the Kennebec the rise and fall of the tide is felt as far as Augusta, 44 
miles from the sea, and before the erection of a dam at that point it was perceptible some 10 miles 
farther. In the Penobscot the influence of the tide extended originally to Eddington, 30 miles 
above the mouth of the river, or, including Penobscot Bay, 60 miles from the sea. In the other 
rivers the tidal portions are less extensive absolutely, and in many of them likewise relatively, to 
the size of the river. The Androscoggin is not affected by the tide above Brunswick 25 miles, 
and the Saco only to Biddeford, 5 miles from the sea. The actual penetration of the sea-water 
is confined within narrow limits. On the Kennebec the water does not contain salt enough to 
support a growth of marine alg above Bath, 12 miles from the sea, though in seasons of great 
*H. F. Mills, C. E., quoted in Wells’s Water-power of Maine, p. 105. 
