FISH PHOTOGRAPHIC EXCURSIONS 161 
tank is placed immediately behind the other, and in it 
are arranged suitable weeds (gathered during the early 
morning fishing excursion). No water runs through 
this tank, and at first it is thick and muddy, and the 
weeds droop. On the platform behind the second tank 
are placed stones, gravel, earth, sods of growing grass, 
or stiff reeds. Beyond is hung up the plain canvas 
background. When the sun is low and casts a long 
shadow, this background must be sufficiently far back 
to be out of the shadows of the tanks. 
The preparation of the second tank and platform 
has probably occupied an hour or more. 
Now leave the tanks for two or three hours. After 
lunch go back, and the change is wonderful! The 
water in the front tank is crystal clear. Possibly the 
fish may be swimming about, but more probably it is 
still sulking on the bottom. The water in the second 
tank has cleared considerably, the weeds have freshened 
up, and every leaf is covered with bubbles of gas; 
and the earth, stones, and clumps of reeds on the plat- 
form behind the tanks (seen through the thickened 
water in the second tank) all appear to be part of a 
pond scene. 
The water in the second tank ought to be just suf- 
ficiently thick to obscure the farthest edge of the plat- 
form as seen on the ground glass when the fish in the 
first tank is sharp in focus. If the water in this tank 
is too thick, run a stream through it for a few minutes 
with the hose pipe. If too clear, stir up the bottom 
L 
