202 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



THE APPARATUS USED IN HATCHING COD. 



The apparatus and metbods employed in cod-culture are tbe out- 

 growth of long experience and study and liave as their special features 

 the closest possible simulation of natural conditions. The apparatus 

 now in general use is tbe so-called McDonald or automatic tidal box. 

 The boxes are constructed in series of 12 or less, tbe number depeud- 



PLAN. 



X. 



O 



^ 



o 



\r 



9. r^ 



* 



A 



Secfion fhrouqh /\-B 



Diagram of Tidal Cod Hatching-Bos. 



g, FEET 



A-B Points where cross-section is taten. 

 a, siphon. 



c, partitions fonning njjper pockets, 

 rf, partition forming space at upper end of 

 compartment. 



e, partition forming space at lower end of 



compartment. 

 /, glass gate. 

 (J, slot between adjoining compartments. 



ing on the size of the hatching-room, the arrangement of the hatching- 

 tables, or other conditions. The Gloucester hatchery has 8 tables of 

 9 boxes each, and Woods Hole 14 tables of 12 each. At Gloucester 

 25,000,000 eggs can be hatched at oue time, and at Woods Hole 

 65,000,000. For a wooden framework to accommodate 9 boxes such 

 as are used at Glouscester the outside dimensions are: Length, 10 



