PROGRESS IN BIOLOGICAL INQUIRIES, 1921. 93 
Stand pipe > sel —- Pend embonrment— 
“Hi, SS 
Ag YY — 
Lgl Oncher i; hlocn—>~ ’ 
Fig. 1.—The Canfield pond outlet, side view. 
Qnchor bloc a 
a 
S Kettle. os 
re 
eat Toner kettle, 
Fic. 2.—The Canfield pond outlet, end view. 
