236 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



than mineral oil. The luminous effect of refined menhaden oil luis 

 been found lo he liiiili Avitli a relatively Ioav consumption, as coin pai-ed 

 witli petroleum. 



The following treatment of menhaden oil in combination with other 

 substances for painting purposes is recommended ])y Andes:" 



Into a wooden barrel are brought 144 liters of good vinegar, 6 kilograms of 

 litharge, and G kilograms of zinc sulpliate; then the barrel is rolled alioiit for a 

 long time, and the liqiiid then poiired into 100 liters of fish oil. The mixture is 

 well stirred, and then left at rest for twenty- four hours; when the clear oil is 

 drawn off. seven-eighths of the original quantity is obtained. Fifty-four liters of 

 linseed oil and 9 liters of turpentine are at once added. The licjuid is left at rest 

 for several days, and then drawn off. The residue is mixed with an equal volume 

 of milk of lime, and used for painting wood and iron which are exposed to the air. 



When whale ajid cod oils are scarce and higli in price menhaden 

 oil is extensively used as a substitute. Its chief competitors are 

 degras, petroleum compounds, aiui lierring oil made in the United 

 States and in Japan and Europe, the latter competing \\ ith it prin- 

 cipally in Europe. For further data in regard to this oil, especially 

 the metliods of manufacture, extent of production, and so forth, see 

 pages 255-265. 



HERRING OIL. 



The herring, including its related species — the sardine, pilchard, 

 sprat, anchovy, etc. — is probably the most valuable and important 

 product of the world's fisheries, not so much on account of the choice 

 nutritive qualities, perhaps, as because of the enormous (xuantities 

 obtained. When the x>roduct exceeds the demands of the food nuir- 

 kets, including those required for salting, canning, etc., these fish 

 furnish excellent material for oil-production. Their utilization for 

 this purpose is by no means of recent origin, the i^roduction of herring- 

 oil in the Bohuslan fisheries of Sweden over a century ago ranging 

 between 1,000,000 and 2,000,000 gallons annually. Nor is it of lim- 

 ited geographical distribution, as the oil is produced to a greater 

 or less extent in nearly every maritime country of Europe, in the lii-it- 

 ish North American provinces, on the northern coast of the United 

 States, in Japan, certain parts of the African coast, etc. 



Since only the surplus or waste fish are used in oil-making, and as 

 the catch fiuctuates greatly, it follows that much variation occurs 

 from year to year in the quantity produced. The figures showing 

 the output in a certain territory are quite unreliable for anv year 

 except the one to which they particularly relate. It is therefore dif- 

 ficult to approximate the product of herring oil throughout the world. 

 It seems probal)l<', however, that a reliable estimate would jilace 

 the average annual jield at not far from 3,500,000 gallons, of which 

 only a small portion is produced in the United States. 



During the fifteen or twenty years preceding 1875, when fish oils 



"Andes: Drying Oils, p. 280, London, 1901. 



