DEVICES FOR USE IN FISH HATCHERIES AND AQUARIA. 



1 031 



consists of a long rubber tube attached, with metal handle and connections, 

 to a blue-tipped pipette on one side and to a rubber bulb on the other. The 

 bulb normally receives its air supply through a small rubber tube which is 

 connected with a metal piston valve inserted in the large tube some 0.60 meter 

 below the bulb. An auxihary air valve in the handle is controlled by a little 

 piston within reach of the index finger of the right hand. 



To use this apparatus have the lower end of the large tube and also the 

 lower piston valve below the water level 

 existing in the trough. Squeeze the bulb 

 with the right hand, press the lower piston 

 with the left, and then, putting the end of 

 the glass tube in the water, release the 

 bulb. Then release the piston and the 

 siphon will have started. The glass tube 

 may be directed at will. If the suction 

 is too strong it may be regulated by the 

 piston in the left hand. 



Should a good egg be picked up by 

 mistake it may be readily replaced with- 

 out waiting for it to discharge at the lower 

 end of the rubber tube. Stop the flow of 

 water by closing the lower piston with the 

 left hand ; then press the bulb to expel the 

 air from the small tube upward into the 

 larger, the mouth of the glass tube being 

 meanwhile under water. If this does not 

 force the egg out of the glass tube continue 

 to hold the piston closed, squeeze the bulb 

 with the right hand, and then with the in- 

 dex finger press the little auxiliary piston 

 at the end of the handle. If now the bulb 

 is released it will fill. Removing then the 

 pressure from the little piston on the han- 

 dle there can be no escape of air at this 

 point when the bulb is compressed, but only backward in the main tube, for 

 the discharge outward is cut off by the closed lower piston valve. The egg will 

 thus be forced out of the glass tube. 



Care should be taken to avoid drawing water into the bulb, but in such 

 event a discharge may be effected by proceeding as just described except that 

 the lower piston valve is in this case left open. 



Fig. 3.- 



-Apparatus for cleaning hatching or rearing 

 troughs. 



