TRANSPORTATION OF SPAWN AND FISHES. 137 



wea-ther the greatest success may be attained in 

 transporting the fry. 



But larger fishes must sometimes be transported, 

 and for this recourse must be had to a transit tank. 

 The Troutdale Transit Tank (Fig. 28) was invented 



FIG. 28. 



by us some three years since, and has always, in 

 competent hands, given perfect satisfaction. The 

 can is constructed of heavy galvanized sheet iron ; 

 to the outside is attached an air-pump, communi- 

 cating by means of an india-rubber pipe with a 

 tube leading to the bottom of the can, which ter- 

 minates in a nose similar to that of a watering-pot 

 pierced with minute holes. By simply working 

 the handle, air is driven in, and being divided into 

 fine bubbles by the nose, completely aerates the 

 water, restoring the oxygen consumed in respira- 

 tion by the fishes. On the interior, about h.alf way 

 between the bottom and top, a ring of strong wire 

 is soldered ; on this can be laid a perforated plate, 



