AQUATIC PRODUCTS AS FERTILIZERS. 265 



The yield of oil varies greatly, ranging from less than 1 pint to as 

 much as 15 gallons or more per thousand fish, or rather for each 22,000 

 cubic inches of fish. As a rule, it is much greater in the autumn than 

 in the spring, and also greater in Northern than in Southern localities. 

 Even in the same locality the fish are very much fatter throughout 

 some years than in others. For instance, the average jaeld of the 

 fish taken in Cliesapeake Bay in 1887 was nearly G gallons to the 

 thousand, whereas in 1888 it was a little over 2 gallons, and early in 

 that season it was less than 1 pint to the thousand fish. Some j^ears 

 ago one of the Shelter Island factoi'ies secured from one lot of fish a 

 yield of 24 gallons to the thousand. The largest yield brought to the 

 notice of the writer was derived from some menhaden that had been 

 inclosed in Shinnecock Bay late in autumn. By feeding in the brack- 

 ish water of that bay these became so fat that they yielded at the 

 rate of 48 gallons of oil per thousand fish. Considering the entire 

 Atlantic coast for a series of ten j^ears ending in 1898, it is found that 

 eacli thousand fish yielded 4.59 gallons of oil and 138 pounds of scrap 

 containing 10 per cent of moisture. During the ten years ending in 

 1888 the jdeld per thousand fish was 4 gallons, and during the six 

 years ending in 1878 it was 5.26 gallons. 



The table given on page 233 shows the total jaeld of menhaden oil 

 on the Atlantic coast of the United States and the average j'ield per 

 thousand fish for each year since 1873. From those figures it appears 

 that the largest yield per thousand fish was G.84 gallons in 1874. The 

 yield in 1887 and also that in 1880 were large, being 6.81 and 6.38 

 gallons, respectively. The smallest yield per 1,000 fish was in 1880, 

 2.62 gallons, and in 1881, 2.79 gallons. 



Not only does the yield of oil vary from year to year, but it also 

 differs greatly in difi'erent sections of the countr3\ As a rule, the 

 Northern fish, or rather those taken in Northern waters, especially off 

 the Maine coast, are the fattest, while those from off the southern coast 

 yield the smallest quantity. In the year 1900, for instance, tlie yield 

 of oil at the Rhode Island factories was 5.76 gallons per 1,000 fish; in 

 New York it was 6.39 gallons; in Delaware 4.92 gallons, and in Texas 

 3.51 gallons to the 1,000 fish. The menhaden taken off the coast of 

 Maine are by far the fattest, and in the few seasons when fish are 

 obtainable there the menhaden fishermen from other States hasten to 

 that coast. In 1888 the Maine fish yielded 11.85 gallons of oil per 

 1,000; in 1889, 10.83 gallons, and in 1898, 9.73 gallons to the thousand 

 measure. Menhaden have not been taken to any extent on that coast 

 since 1898. 



TREATMENT OF THE SCRAP. 



As it leaves the i)ress, fish scrap contains 45 or 50 per cent of water, 

 whicli can not be removed by compression owing to the gelatinous 

 condition of the fiber. Although suitable for immediate applica- 

 tion as a fertilizer, the moist condition of this scrap renders it unde- 



