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FOUNDERS OF OCEANOGRAPHY 



in the sardine fisheries of France, and from the swim-bladder 

 isinglass is made. 



The herring family (Clupeidae) includes the sprat, the 

 pilchard (the young of which is so familiar in the preserved 

 form of " sardines "), the anchovy, and, most important of 

 all, the true herring — that wonderful fish which, as the 

 mainstay in the fourteenth century of that powerful trading 

 and political organization the Hanseatic League, and after 

 that of the Dutch commercial and naval supremacy, may be 

 said to have played its part in determining the history of 

 nations and the fate of empires. All these Clupeoid fishes 

 are noteworthy for the relatively large amount of fat they 

 contain in the form of minute globules of oil disseminated 

 through their flesh, while the cod and its allies are almost 

 destitute of fat. The herring, however, has a very different 

 amount of fat in its composition in different states and at 

 different times. For example, the winter herring, in poor 

 condition, may have only 4 or 5 per cent, of fat, while the 

 spawning summer herring may have from 30 to 40 per cent. 

 The average of three series of Manx herrings caught in the 

 summer of 1917 and cured in brine gave the following analy- 

 sis, ^ and may be contrasted with the composition of the cod : — 



Other Manx herrings, however, caught in September, 

 1917, cured in brine and analysed in winter, gave as much 

 as 32*72 per cent, of oil (fat). 



It is this relatively large amount of easily digestible fat 



^ By Professor James Johnstone of the University of Liverpool 

 (see, for further details, Lancashire Sea-Fisheries Laboratory Report 

 for 1917). 



