FISHERIES OF THE UNITED STATES. 215 



HATCHmG-HOUSES. 



42811. Model of Druiil Hill hatching-bouse, »S:c.— Coutiuued. 



with valves that the water can bo conducted into the ponds be- 

 low the house without entering the liltering tank should it be 

 desirable. The water after passing through a series of flannel 

 filters is discharged from the filtering tank into a reservoir tank 

 of the capacity of about twelve hundred gallons. From this 

 tank the water is piped under the floor, which is a Schillenger 

 pavement, to the several hatching troughs, and to the tables 

 in the octagonal extensions. These pipes are admirably ar- 

 ranged with stojj-cocks, so that any portion of the ai»paratu8 

 can be operated without regard to the rest of the building. 



In addition to the supply from the spring there are pipes by 

 means of which an unlimited amount of water can be tluowu 

 into the filtering tank or ponds from the high service reservoir 

 which is on the hill to the west of the hatching house. The 

 water from the reservoir being influenced by the temperature 

 of the atmosphere, and that from the spring being invariable, 

 by mixing different x)roportions, the temperature of the water 

 used can be either raised or diminished at will. The pipes which 

 conduct the water to the tables on which the Ferguson jars are 

 operated, are furnished with |-of-an-inch spigots, over which 

 rubber tubes are slipped, for the purpose of introducing water 

 into the jars. 



On the floor of the house is arranged the following apparatus: 



A. Ferguson jars. 



B. Flights of Coste tray. 



C. Troughs of Williamson's patent. 



D. Troughs of N. W. Clark's patent. 



E. Green & Holton hatching box. 



F. Aquarium. 



G. Reservoir tank. 



H. Porcelain-lined sinks. 

 In this house have been hatched : 

 2,497,140 California salmon. 

 89,881 land-locked salmon. 

 331,980 brook trout. 



HATOHING-TROUGHS AND BOXES, STATIONARY. 



39498. Model of the first hatching-box used in America, by Dr. Theodatua 

 Garlick, in the year 1853. Dr. T. Garlick, Bedford, Ohio. 



26936. No. 20. Model of hatching-troughs and trays in use at the United 

 States salmon-breeding stations at Bucksport and Grand Lake 

 Stream, Me. Scale, full size. C. G. Atkins. 

 The eggs to be hatched are placed on the wii-e-cloth trays. 



42812. Model of Clark's hatching-box for all the salmonidiB. The eggs are 



placed upon the screens and the water flows in from above .and 

 out below. Patented by N. W. Clark. F. N. Clark, Northville, 

 Mich. 

 42934. Model of the Holton hatching-box for all the salmouida>. The eggs 

 are placed upon all the screens except the top one, .and the water 

 flows in from below and out at the top. Patented by Marcellna 

 Holton. Seth Green, superintendent. New York. 



