MANUAL OF FISH-CULTURE. 127 



house if desired. The couuectiou is made by a thin brass nipple with 

 the siiiiie interior diameter as the piece of rubber tube to be joined by 

 slipping it into the longer piece and lashing it on the outside with twine, 

 leaving about three-quarters of an inch outside to slip into the shorter 

 piece after the siphon is started. The other end of the long tube is 

 connected with a like piece of brass tubing, bent to a quarter circle to 

 prevent the rubber tubing from kinking, to and through the center of 

 a wooden float some 12 inches in diameter and 1 or 2 inches thick. 

 This is placed in a tub or large pail ; the short siphon is started and 

 connected as above described, and the long siphon is in working order. 

 The water runs over the rim of the tub into the sluice, over which it is 

 placed, and the eggs settle to the bottom. A whole hatchery can be 

 operated without moving the tub, although it is better to raise it 5 or 6 

 feet from the floor for the upper rows of the jars, as the suction 

 otherwise becomes a little too strong and liable to injure the good eggs 

 when passing too rapidly through the tube. 



For convenience and for economy of space and water, the hatching 

 jars are arranged in tiers, constituting what is known as a "battery." 

 The structure of a battery, with its complicated system of supply 

 and waste troughs and with the jars and their attachments, is rather 

 difficult to describe clearly, but may be understood by reference to 

 plate 35, at the end of the volume. 



Each battery is divided into two sections, which have four rows of 

 jars on each side, setting on shelves 3 feet apart. The water is admitted 

 through an iron pipe to the uppermost cross-tank; from there it runs 

 into the uppermost supply-trough, which, like all the others, is 13 inches 

 wide and 9 inches deep, inside measurements. The iron pipe is provided 

 with a ball-cock, regulating automatically the supf)ly of water. The 

 supply-troughs are from 22 to 34 feet long, the upper ones being the 

 shortest and the lower the longest. The first supply-trough has a row 

 of brass cocks on either side taking the water 1 inch from the bottom. 

 A half-inch rubber tube, (5 inches long and forming when adjusted a 

 quarter circle, is slipped over the outer end of the cock and the upper 

 end of the iron tube, which is inserted in the jar. The water flows from 

 this upper supply trough, which may be called IsTo. 1, in section No. 1, 

 through the cock, rubber tube, iron tube, and jar, from which it is dis- 

 charged into what may be called waste-trough No. 1, which is directly 

 below supply-trough No. 1. This discharges its water into a cross-tank, 

 the second from the top, which carries the water across to supply -trough 

 No. 2, which is in section No. 2. This supplies the second of the eight 

 rows of jars, through which all the water passes, and after passing 

 through the jars, as before described, it emi^ties into waste-trough No. 2, in 

 section No. 2, which carries it to cross-tank No. 3, which in turn carries 

 it across and delivers it to supply-trough No. 3, which is in section No. 

 1. Thus the water goes back and forth from one section to the other, 

 dropping a step at each passage, until it finally enters the fry- collecting 

 tank on the floor, which is 3J feet wide, feet long, and 2 feet deep. 



