718 REPORT OF COMMISSIONEii OF FISH AND FISHERIES. 



After taking away the natural oil the livers are put to cook, and they 

 extract successively the " brown pale oil " {Jiuile brune 'pdle)^ and the 

 " brown oil " {Imile brune). The latter is an inferior i^roduct, employed 

 principally by tanners, and is shipped away in oak or fir casks. The 

 residuum is employed as manure, and is much sought after. 



The extraction of the medicinal oil is carried on by separate manu- 

 factories. They use alwjiys fresh livers, carefully washed and dried. 

 They are placed in tin-plate boxes with double walls, with a circula- 

 tion of steam or warm water between. The oil is then drawn off' and 

 filtered, as fast as it is produced, through paper filters, then shipped 

 away in tin cans or oak barrels. The residuum, by further cooking, 

 furnishes common oil {huile brune ou verte), which is likewise used in 



the arts. 



6. Roe. 



A third product of the cod-fisheries is the roe, which, in the eight- 

 eenth century, was used for the first time as bait for sardine-fishing 

 upon the coasts of France and Northern Spain. The roe is prepared, to 

 some extent, by the fishermen themselves, but it is otten sold fresh. 

 Part is used at the place of capture as bait for the cod ; the rest is 

 salted for exportation. For salting the roe the gray salt from France was 

 formerly used, but they now employ white salt from Cadiz. 3?he salting 

 is done in barrels with holes bored in them to permit the brine to run 

 out, so as to leave the roe always comparatively dry. The best roe is 

 that gathered at the beginning of winter. Later it becomes less and 

 less good, and after the spawning season there remains only the empty 

 ovary. The high price of the roe in France has been the cause of their 

 seeking to replace it by substitutes. Dr. Morvan has succeeded in part 

 by the introduction of the African locust preserved in salt, as bait. 

 But as these locusts are only procurable when there has been a grand 

 invasion of them into Algeria, this product was not one that could be 

 relied upon, and, besides, its price was not much lower than that of the 

 Norwegian roe. The same Dr. Morvan and his associate, Mr. Delasalle, 

 an old sea officer, had more success with the roe called Douarnenez ; 

 they manufactured it with the remains of meat and fish as well as 

 cakes of an American ground-nut {Aracliide) thoroughly mixed together. 

 The i:)roduct was compounded with the Norwegian roe in the propor- 

 tion of 3 to 1, which caused a sensible saving, the price of the new mix- 

 ture being 30 to 35 francs against CO. The success, however, of this 

 preparation, has, it is said, been but temporary, and the diminution 

 in value of the Norwegian roes in 1877, due to the abundance of the 

 article, seems to have diminished its use. 



7. Otheh species of the genus gadus. 



It is proper to add here some details upon other fisheries which form 

 an important element of the work on our coasts, and which contribute 

 toward maintaining the markets of the interior and exterior. Hitherto 



