stantly cruise for their supplies, making trips from Block Island to the coast of Maine, touching at Noman's Land, Martha's Vineyard, Nan tucket, Cape Cod, and other intermediate points, to see the fishermen and purchase their catches. Dr. Sims, the head of this business, was the medical director of the Third Army Corps at the close of the rebellion, to which he was ap pointed after serving a year as surgeon on the staff of General Hooker, and is a gentleman of great business capacity and superior intelli gence.-[Island Review. "PACIFIC GUANO COMPANY, "Woods Holl, Mass., October 8, 1877. "DEAR SIR: Yours 2d at hand. An improved process for the treatment of fish is now being tested by myself and others. Experiments reveal to us that the fish can be preserved, and that we are able to get a scrap from them of higher grade in ammonia and a dry powder. The fish are treated with bisulphide of carbon and of hydrocarbons as benzine. The process removes all the oil and leaves the product in a dry powder. The by-product of oil is about eighty per cent. more than by kettle and press, and goes far towards paying expenses. "The dry scrap as now obtained from menhaden yields on an average, 10.50 per cent. ammonia (NH,); by the new process 14 per cent. ammonia (NH3). "We are erecting a building 85 by 40 feet, 34 feet high, to fully test the process, and expect to be in working order in December. I inclose an article taken from the Nantucket paper. You can no doubt give us valuable information in regard to the habits of the shark, their breedingground, &c. The fishermen represent a supply off Nantucket that can be taken with hook and line. "In our business here we consumed for the year 1875-76 708 tons dry scrap (menhaden), value $20,164; 2,338 tons crude scrap, value $31,682; producing 13,010 tons soluble Pacific guano; 1876-77, 2,176 tons dry scrap, value $57,784; 5,188 tons crude scrap, value $62,248; producing 11,398 tons soluble Pacific guano. Our works at Charleston usually consume one-third less than here. "The menbaden scrap is now dried more extensively than ever. The solar heat and hard platforms found to be the cheapest and most satisfactory process. We purchase what dry scrap we can in place of crude scrap. I send you the only document published bearing on the history of this company. "Yours, truly, "Prof. G. BROWN GOODE." "A. F. CROWELL. 7. Methods of calculating costs of valuable ingredients of fertilizers.* The method referred to on page 235 consists in comparing different fertilizers by the costs per pound of the valuable ingredients at the prices at which the articles are sold. The way in which these computations are made here may be explained as follows: ammonia containing 20 per cent. Twenty per cent. is equivalent These 400 pounds of nitrogen Take first a simple case, a sulphate of of nitrogen, and sold at $100 per ton. to 400 pounds in a ton of 2,000 pounds. cost $100. One pound will therefore cost $100 ÷ 400 = 25 cents. Now, a more complicated case. Suppose a superphosphate to contain valuable ingredients (and that, for convenience, we indicate the latter by abbreviations), as below: Soluble phosphoric acid, (Sol.).......10 per cent.=200 pounds in ton, Insoluble phosphoric acid (Ins.) Nitrogen (N.) 2.5 per cent.= 50 .... 3 per cent. 60 = that it be sold at $40 per ton, and that the values of the ingredients are in the ratios of Sol. 15, Ins. 6, and N. 25 cents per pound. The problem will be to find a series of values in the ratios 15: 6: 25, which, multiplied by the respective numbers of pounds of Sol., Ins., and N. in a ton, will give three products, whose sum will be $40. The method employed here for solving the problem is as follows: The assumed rate for Ins. was 6 cents, that for Sol., 15 cents, or 2 times as much, and that for N. 25 cents, or 4 times as much. Multiply the number of pounds of Sol. in a ton by 2, and that of N. by 41, and add the products to the number of pounds of Ins., and the sum will be the number of pounds of Ins. which would have the same value as the Sol., Ins., and N. actually present taken together. Divide the whole cost by this sum and the quotient will be the cost of one pound of Ins. This multiplied by 2 will give the cost of one pound of Sol., and by 41 will give the cost of one pound of N. The calculations for the above case will be: The price per ton, $40, divided by 800, gives 5 cents, the cost of one pound of Ins.; 5 x 21=123 cents cost, of one pound of Sol. ; and 5X 4120%, cost of one pound of N. *From report of Connecticut Agricultural Experiment Station, 1876, W. O. Atwater, director. The proof of the correctness of these figures is plain : Soluble phos. acid, 200 lbs., @ 123 cents, would cost.. 50 lbs., @ 5 66 60 lbs., @ 20% 66 66 66 $25 00 2.50 12.50 $40.00 Total valuable ingredients in ton would cost Another method for calculating the costs of ingredients, which consists in estimating the value of one at an assumed rate per pound, subtracting its total value, as thus computed, from the whole cost, and divid ing the remainder by the number of pounds of the other ingredients to get the cost of the latter, is too simple to require further explanation here. In valuations current in this country, nitrogen in these substances has been reckoned as worth all the way from two to five times as much as phosphoric acid, pound for pound. Considering the fact that the nitrogen is generally in quite readily, and the phosphoric acid often in very slowly available forms, there is ground for varying ratios. A full dis cussion of this subject would require more space than either the knowl edge at our disposal or the necessary limits of this article would permit. In brief, however, I do not find it easy to see why, if nitrogen is worth only about twice as much as phosphoric acid, pound for pound, when both are in their most available forms, it should be worth three or four times as much, as is sometimes assumed, in bone, in which both occur in much less available forms. Too little is known at present of the effect of decomposing nitrogenous matter in bone, fish, castor-pomace, and the like, in dissolving, diffusing, and otherwise rendering avail. able the phosphates with which it is so intimately connected, to enable us to form any accurate estimate of its value on this account. I confess that in the light of the little knowledge that we do have it seems to me more just to preserve ratios of valuation of nitrogen and phos phoric acid in bone the same, or nearly the same, as in the most avail. able forms. In fish, animal refuse, and other materials which contain considerable nitrogenous matter other than that so intimately mingled with the phosphate, and in a form probably more ready to decompose, it seems reasonable to give the higher relative value to nitrogen. In view of such considerations as these, the costs of nitrogen and phosphoric acid in the tables in this report have been calculated on the basis of ratios as follows: In fish, slaughter-house refuse, and castor-pomace-Nitrogen: Phos phoric acid :: 24: 1. In bone-Nitrogen: Phosphoric acid :: 2 : 1. In superphosphates the costs of the ingredients are calculated on a basis of ratios as per the valuations used in the last report of the sta tion, to wit: Nitrogen, 25; phosphoric acid, soluble in water, 15; solu ble in ammonium citrate, 10; insoluble, 6. In Peruvian guanos the same rates are adopted as for the superphos phates, the additional ingredient potash being rated at 8. The prices are those at which the articles have been sold, or offered to farmers during the year at the places of sale; the lower rates in large quantities, lots of a ton or more, for cash; the higher one for smaller lots, or on time. In addition to the analyses and valuations given in the text of the report, the following are presented as indications of the actual condition of the fertilizer market in respect to three most important classes of commercial fertilizers-nitrogenous superphosphates, Peruvian guanos, and fish manures. The prices given are those which prevailed in 1875-'76, and are in some cases a trifle higher than now rule. 32 F |