Fish refuse and kinds of fertilizers made therefrom. 290. It is of interest for us to consider here the "scrap" or pomace left from the manufacture of the oil, and its uses. The fish-refuse enters our markets in several different conditions. The following have come under my observation: 1. "Crude stock," "green scrap," "chum," or crude pomace. 2. "Half dry scrap" or half dry pomace. 3. "Dry scrap" or dried fish. 4. "Dry ground fish-scrap," dry ground fish or "fish guano." 5. Fish guano from which the most of the fat has been extracted by spe cial processes. 6. Acidulated fish. 7. "Fish and potash salts." 8. Fish mixed with superphosphates in the form of "ammoniated" superphosphates, sometimes called guanos. No. 1 is the raw material as it comes from the press. No. 2 is the form it assumes after partial drying. More or less fermentation is apt to take place during the drying. This is often accompanied by considerable loss of nitrogen in the form of ammonia. Large quantities of this "half dry scrap," "half dry pomace," or "fish pomace," as it is variously called, are used by farmers along the coast where menhaden are taken. No. 3 is the coarse scrap dried by the sun's heat or artificially. This also is used in large quantities by farmers near the coast. No. 4 is prepared by grinding the dried scrap. It makes a reasonably fine, dry, quick acting, and excellent fertilizer. The green scrap or crude guano generally contains 55 to 60 per cent. of water. The half-dry scrap contains 40 to 50 per cent. of water. The dry guano contains 10 to 20 per cent. of water. The following measurements and estimates are said to be in use among menhaden manufacturers: 1 ton (2,000 pounds) is reckoned the weight of 3,000 fish. 23 tons of fish yield 1 ton (40 per cent.) of green scrap, chum, or crude pomace. 3 tons of fish yield 1 ton (33 per cent.) of half dry scrap. 5 tons of fish yield 1 ton (20 per cent.) of dry scrap or guano. One thousand menhaden, weighed by Mr. Dudley, president of the Quinnipiac Fertilizer Company, at Pine Island, June 12, 1877, weighed 685 pounds. Mr. Dudley has kindly furnished the following statements: "We take them from the fishermen at so much per thousand, reckoning 22 cubic inches per fish. One thousand fish, measuring 22,000 cubic inches, weighs 667 pounds (3,000 to the ton). "6,000 to 7,000 fish make 1 ton of The last I weighed took 6,700 for a ton. 65 per cent. of moisture. green scrap' from the press. Green scrap contains 55 to "10,000 fish, on the average, yield 1 ton of half dry scrap, containing 40 to 50 per cent. of water. "15,000 fish, on the average, make 1 ton of sun-dried scrap, containing 10 to 20 per cent. of moisture." "In regard to prices for the past ten years, we have sold fish scrap or half dry fish, as it is called in Connecticut Valley, in car-load lots in bags, free on board cars at New London or New Haven, as follows: "1869, $20 to $24 per ton; 1870, $23 to $25 per ton; 1871, $20 to $25 per ton; 1872, $16 to $19 per ton; 1873, $18 to $20 per ton; 1874, $19 to $23 per ton; 1875, $15 to $17.50 per ton; 1876, $17 to $20 per ton; 1877, $14 to $17 per ton; 1878, $17 to $18 per ton. "Prices in bulk at factory are usually about $3 per ton lower than at New Haven, owing to cost of packages, labor, and freights. Dry ground fish guano was retailed ten years ago at $55 per ton, now at $40 to $42.50; wholesale, $5 per ton less." Methods of manufacture and need of improvement.-Statements by Prof. C. A. Goessman. 291. The following statements from the Third Annual Report of the Massachusetts State Inspector of Fertilizers, Prof. Goessman, who has given a great deal of attention to the subject of fish manures, are of special value in this connection. Professor Goessman gives an analysis of a sample of dried fish scrap obtained at the chemical works under the charge of Hon. S. L. Goodale, at Booth Bay, Me., where large quanti ties of fresh scraps were delivered direct from the press of an adjoining fish-rendering establishment. It was deemed a particularly fair sample of a well-rendered and carefully-dried menhaden fish. It contained 10 per cent. of water, 70.75 per cent. organic matter, 18.25 per cent. ash, 8.46 per cent. phosphoric acid, and 8.14 per cent. nitrogen. "About one third of the entire phosphoric acid proved to be scluble in citrate of ammonia. Ether abstracted at ordinary temperature 18 per cent. more of a thick, highly-colored, oily mass. "The following rules of rendering the fish were stated as being cus tomary in the establishment above mentioned: the fish were boiled for about one-half to three-quarters of an hour, by means of steam of from 70 to 80 pounds' pressure, in large wooden tanks with false bottoms; and subsequently, after the soup had been withdrawn, subjected to a pressure of about 115 to 120 pounds per square inch. The fish mass, in cousequence of its gelatinous condition, retains usually still from 50 to 55 per cent. of moisture. In a large fish-rendering esfabishment near New York City, I noticed that the boiling of the fish was continued only 25 minutes, with steam of 50 pounds' pressure, and the rendered fish mass subsequently treated with 160 pounds' pressure per square inch. "The soup, which contains besides the oil more or less of the glueproducing, soluble nitrogenous matter of the flesh and the bones, is at pres ent discharged after, by means of settling-tanks, the oil has been care fully removed. This practice causes a considerable waste of nitrogen. The yield of oil differs, often widely, even during the same season, being, it was stated, usually highest during autumn. The rendering begins usually in May or June, and closes late in the fall. The quality of the fish refuse in general, independent of its moisture and mechanical condition, depends, quite naturally, to a large extent, on the following cir cumstances: "First. On the kind used and whether entire or in part. "Second. On the peculiar mode of rendering. "Third. On the time when the fish are caught. "Fourth. The course pursued in keeping and preparing the refuse for the general market. "Each of these circumstances exerts an influence of its own on the composition of the fish guano. "Judging from general appearances, but little attention is paid thus far to the first three conditions; the influence of the last one is, more or less, fully understood, yet not satisfactorily controlled. A main difficulty, no doubt, arises from the irregular arrival of large quantities of fish at one time during the season; and the means, which are at present usually employed to meet this difficulty, are, quite frequently, inadequate to the demand. Many manufacturers of fish-oil consider it, therefore, apparently a safer proceeding to dispose at once of their crude stock at low rates than to run the risk any longer. Without questioning the soundness of their course of action, in case of limited pecuniary means, there seems to be no valid reason why improvements should cease here as long as it is daily demonstrated that it pays well to collect animal refuse matters from all over the country and to work them into valuable concentrated fertilizers. "Nobody familiar with the nature of a good fish guano considers it less efficient for agricultural purposes than any other animal refuse matter of a corresponding percentage of phosphoric acid and nitrogen. In fact, all true guanos, the Peruvian not excepted, owe their most valuable constituents, in a controlling degree, directly or indirectly to the fish. "Our fish guano consists of the entire body of the menhaden fish, which has been deprived purposely of its main portion of fat, and, incidentally, more or less completely of its soluble nitrogenous matter. The more the flesh predominates, the more the fat has been abstracted without the application of an excessive heat, as far as time and degree are concerned, the higher will be the commercial value of the residue of the press in case of an equal percentage of moisture. The flesh of the fish, like that of our domesticated animals, contains on an average 15 per cent. of nitrogen. The same close approximate relation exists between the bones and the textures of these otherwise widely differing classes of animals; for the fish-bones and the scales consist, mainly, of a varying quantity of cartilaginous (nitrogenous) matter and of (tricalcic phosphate) bone phosphate. "To produce a fish guano which contains in a given quantity the largest possible amount of nitrogen, must be the principal aim of the manufac turer. It brings the highest pecuniary compensation; for one percentage of nitrogen is commercially equal to 4 per cent. of phosphoric acid. "During the past, it is true, there has been little inducement for considerations of this kind on the part of the manufacturer, because prac tically there has been scarcely any serious discrimination on the part of the consumers regarding the exact relative chemical composition of the various fish guanos offered for sale. "The future prospect of this branch of home industry depends, in an unusual degree, on the exertions which hereafter shall be made, on the part of the manufacturers, to meet the present more exacting conditions of the trade in fertilizers. "To derive any full benefit from the capital invested renders it ad visable, for all parties pecuniarily interested in the fish guano manufacture, to favor a closer scientific investigation into the changes which the menhaden fish undergoes during the customary mode of ren dering. "Loss of nitrogenous matter, in consequence of misapplication of heat, seems to be not always compensated for by an increase of the yield in oil. "The latter, when left in the fish mass in an undue proportion, reduces, to say the least, the commercial value of the guano by adding a worthless matter, which may affect seriously the analytical results, as far as its percentage of nitrogen is concerned. To heat the fish to a higher temperature, or for a longer period of time than is required to secure the largest possible amount of oil, reduces, invariably, the commercial value of the fish mass for agricultural purposes. A few subsequent an alytical statements, regarding the composition of fish, and the degree of the changes which they may suffer by steaming and rendering, may serve as a practical illustration of my previous remarks." "A well-dried and finely-ground fish guano is one of our best substi tutes for Peruvian guano, and ranks equally high with the best quality of animal dust from our butcher refuse establishments. It deserves the liberal patronage of farmers wherever a rich nitrogenous phosphate is called for. “I have shown in a previous report, that, as a general rule, the high grades of superphosphates are cheaper than our low grades; the same rule applies to nitrogenous materials. "The recent changes in our fertilizer trade tend to stimulate improvements in the modes of their manufacture, by rendering true merits prominent, which, as a natural consequence, secures a reliable patronage only to the best quality. We are not yet suffering from an overstocking of our fertilizer markets on account of overproduction of home-made fertilizers obtained from suitable home resources. "Millions of dollars are annually sent abroad still, for the importa tion of materials, which, in their crude form, are by no means better than what we have in abundance at home. "The manufacture of fertilizers has become in the same degree an art, as agriculture itself has justly assumed the claim of being a sci ence. "The production of fish guano, although respectable already, as far as quantity is concerned, is thus far but incidental to the menhaden fish-rendering industry. "It remains still an open question whether our resources for the manufacture of fish guano do not extend beyond that branch of industry." Statements of Mr. Maddocks.—Manufacture in Maine. 292. From the fifth report of the secretary of the association of the menhaden oil and guano manufacturers of Maine, Mr. L. Maddocks, which is devoted to "The Menhaden Fishery of Maine," the following quotations are taken. The manufacturing processes are those prevalent on the Maine coast, particularly in the region of Booth Bay: "The fish [as brought in by the fishing vessels] are discharged into a car running upon a rail-track to the second story of the factory, and thence poured into tanks below, holding sixty to seventy-five barrels. These are filled one-third with water, steam turned on, and the fish cooked an hour, or until the albumen is coagulated, and the oil-cells broken. The cooked mass, after draining, passes into presses worked by hydraulic power, and is subjected to the pressure of a hundred tons per square inch, the oil and water flowing out and being collected in vats. The oil is then drawn off, clarified by settling, barreled, and is ready for market. The residue, called chum or scrap, is usually stored in the lower story of the factory until taken away by the purchasers, chiefly the manufacturers of ammoniated superphosphate of lime. "The following figures will give more definiteness to the statement: "One hundred and ninety-five pounds of fish make a 'barrel.' "One barrel yields about two and a half gallons of oil, or eighteen and three-quarter pounds." "One barrel yields about eighty pounds of fresh chum or scrap. “These are average results of the manufacture as now conducted in this State. The amount of oil realized varies from one gallon per barrel of fish, early in the season, to four or five gallons in September." "The scrap contains, on the average as it comes from the press, 55 to 60 per cent. of its weight in water, and sometimes more. This is of course worthless for fertilizing purposes. It also contains from 12 to 20 per per cent. of fat or oil, which is equally worthless for manure. "As now generally managed, the scrap remains in large heaps until shipped, in autumn or winter, to the points of manufacture into superphosphate. In this time a portion of the oil and water leaks away, so as to leave about 10 or 15 per cent. of the former, and 48 to 53 per cent. of the latter. The elimination of the water is an advantage, but the |