BULLETIN OF THE UNITED STATES FISH COMMISSION. 101 



water several hours to flow out, so tbat the person iu charge of the fish is 

 not worked too hard. This apparatus has been very successfully used in 

 the journey from Trieste to Berlin, which lasts 72 hours. Vessel !No. 1 con- 

 tains 24 hundred- weight, and the two others half that quantity. If there 

 are enough persons to superintend and do the work, vessel No. 3 can be 

 dispensed with by pumping water from vessel Xo. 2 into vessel No. 1 

 direct, through tube C, which should be provided with air-tubes, and 

 which must reach to the bottom of the vessel. I prefer this method to 

 the first-mentioned one, as in consequence of the greater pressure of the 

 water, produced through the pump, larger quantities of air can be intro- 



«5 



Fig. 4. 



duced into the water. It is also possible to introduce air simultaneously 

 into several vessels by one pump, by means of several narrow tubes, which 

 must of course be furnished with air- tubes. In the projected railroad car 

 for transporting fish the airing of the various transporting vessels is to 

 be accomplished on this principle. 



In transporting fish any considerable distance some precautions should 

 be observed, which I must briefly mention in conclusion. If possible, 

 only perfectly sound fish should be transported ; these fish ought to be 

 kept confined for some time prior to being transported ; a few days be- 

 fore the journey is commenced no food should be given to them, so that 

 there is no danger that the water becomes impure by the vomit or ex- 

 crements of the fish. It is advisable, if any way possible, to change the 

 water during the journey. This is of course easier with fresh-water than 

 with salt-water fish, as it is nearly always possible to obtain good spring 

 water during the journey. It is more difficult, but not impossible, to 

 change sea water during the journey. For this purpose concentrated 

 salt water, such as is for sale at the Berlin Aquarium, should be taken 



