44 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
time of visiting Lake Sammamisli the water had overflown the channel of the slough 
from a quarter to a half mile; its average width for the part visited is less than 100 
feet, in some places not over 50 feet. Its length is about 12 miles; its course, as indi- 
cated on the map, is very crooked, and it is navigable for small craft only. 
Temperatures . — The water temperatures during our investigation varied but little, 
and in many parts of the lake there is no difference. In the first line of soundings 
run across the lake the surface and bottom temperatures were the same. The weather 
at the time was rainy, misty, and cold. In the second line a difference of 1° was 
found in two places, each in a depth of 90 feet. At the surface the thermometer 
registered 45° and at the bottom 44°. In the third line the depths were from 33 to 92 
feet, with no variation in temperature. The fourth line, run the same day, shows in 
eight different soundings 45° at the surface and 44£° at the bottom. The fifth line, 
run across the head of the lake, showed no difference; but in a number of soundings 
taken on the west side, near where a small brook empties into the lake, the water was 
1° warmer at the surface than at the bottom. The depths here were comparatively 
shallow. The last line of soundings run, which was across the foot of the lake, also 
showed the water to be 1° warmer at the surface than at the bottom. This difference 
may possibly have been because the weather was warm and pleasant, while most of 
the time, when the other soundings were taken, it was rainy and foggy and the 
temperature of the air from 44° to 50°. On this day, January 6, it registered 60° a 
greater part of the day. 
Where the water at the surface was warmer than at the bottom it was found that 
the warm water extended from 5 to 8 feet below the surface ; where the temperature 
at the bottom was warmer than at the surface the water was constant from 15 to 18 
feet from the bottom. The thermometer was let down at various depths, in most 
cases at intervals of 10 feet, no variation in temperature being noticed until the above 
distance from the bottom was reached. In a few places, however, within 10 feet of 
the bottom the water remained constant. 
Condition of water . — In the fall and winter, when the lake is high, the water is con- 
siderably discolored by vegetable matter and sediment washed from the surrounding 
hills and brought down by the swollen creeks. This gradually disappears as the rain 
ceases, after which the water becomes clear. The fish then bite better than at any 
other time, there being less food in the water for them to subsist upon. 
Lake Sammamish, like Lake Washington, never freezes over. When the weather 
is unusually severe skim ice sometimes forms near the edge in shallow places, but the 
deep water does not freeze. 
Fishing trials . — From December 31 to January 6 sounding, taking temperatures, 
collecting with surface tow net, and fishing with gill nets and troll were carried on. 
The weather most of the time was stormy. Fishing with gill nets was unsuccessful. 
They were set in various places and in different depths, visited twice each day, and 
in the evening set iu a different place. Inquiries were made of fishermen as to where 
fish would most likely be found, but nothing was caught. A trawl was the only 
stationary apparatus used that captured anything, and this caught only one chub and 
a blob. 
Fishing with troll line was fairly successful, five cut-throat trout being taken. 
The weather was unsuitable for this kind of fishing. To meet with good results the 
weather should be moderate and much warmer than it was during the time these trials 
