344 THE SEAS 



the fish can be utilized. Heads, fins, bones and entrails, in 

 fact all that remains of the fish after they have been 

 prepared for market is taken to the meal-making factory. 

 Until recently the great drawback to these factories has 

 been their odour, but now an odourless process has been 

 invented so that factories can be built in the big fishing 

 ports in close proximity to the harbours so that no expense 

 is incurred in transport of the offal. Into one end of the 

 plant is placed the fish remains and from the other comes 

 the clean dry fish meal, ready to be packed up and sold. 

 The offal is first passed through a chamber in which it is 

 heated and dried by means of steam pipes. After this 

 prolonged heating the mass becomes thoroughly sterilized. 

 The vapours and smells arising inside the chamber are 

 carried off and dissolved in special solutions. The dried 

 remains are then passed on to another chamber in which 

 they are crushed and reduced to a fine powder. The 

 meals thus obtained are of great value as food for cattle 

 and poultry. A German firm has recently produced an 

 extract from cods' heads which is to all appearances 

 similar to meat extracts, and which probably is just as 

 nourishing and can be produced at a fraction of the cost. 



Fish scrap can also be dried and used as fertilizers. 



Glue is obtained chiefly from such fish as the cod, 

 haddock, and hake, and is a product of the fish's skin. 

 The material is thoroughly washed to remove all traces 

 of salt and then placed in steam extractors. 



Isinglass is a pure gelatinous substance obtained from the 

 swimming-bladder, or " sounds," of certain fish. Although 

 the best material is obtained in Russia from the sturgeon, 

 very good quality isinglass can also be manufactured from 

 the hake. It is used chiefly for clarifying wines, although 

 it is also used in the making of certain glass and diamond 

 cements. 



