680 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



The water whicli comes from springs at tlie bottom of tlie pouds is 

 cliiefly used for supplying- tlie different spawuiug-ponds, marked A, and 

 the ponds for hardening the skin of the lishes {''■ Hautlidrtungs-TeicW^), 



PLAN OF THE OLDENBURG ESTAULISHiffiNT FOR HATCIIIMG GOLDFISH. 



A, A, A. Spawniuf; ponds. B. Rearing ponds. C. Ponds for skinhardeniug (?). D. Shallow 

 coloring pond. E. Keservoir. F. Injector and niacliinoliousc (contains an engine of ten-horse 

 power, which is connected with a machine of three-horse power). G. Artificial stieam or canal. 

 a. Open supply pipes. 6. Principal discharging canal, c. Waste-pipe leading into A. d. Eel 

 pond, e, e. Tool-houses. 



l^'. B. The dotted Hues, as also the short parallel lines, indicate covered pipes. 



marked C, for although the spawniug-ponds are, by subterranean pipes, 

 connected both with the reservoir and with the hatching-ponds near the 



