vance has been taken by Messrs. Hobson, Hurtado, and Co., agents of the Peruvian Government for the sale of Peruvian guano in this country, in the preparation of different brands of guano, of uniform though different composition, giving the analysis on each bag, and selling them at prices based upon the guaranteed percentages of valuable ingredients. Fish-Scrap Is assuming more and more importance as a fertilizer. Its value is due chiefly to its nitrogen, and in a less degree to its phosphoric acid. Analyses of seventeen samples are given in the Connecticut Experiment Station report referred to. These were sold at prices such as to furnish nitrogen to the user at from 9.4 to 22.1 cents per pound; while in ammoniated superphosphates and the like, as ordinarily sold, the farmers were paying from 20 to 45 cents per pound for their nitrogen. Unfortunately, fish-manures are often ill prepared; their manufacture and use are poorly understood; and they are frequently applied in ways that involve great waste. Fermentation of Fish-Guano. The increasing importance of fish and bone manures in German agriculture has led Dr. Pagel, of the Experiment Station at Halle, to undertake a series of experiments to gain light upon the best means of preparing these for use. He recommends very strongly the plan of fermenting them with urine: "The method of fermentation furnishes a most excellent means for transforming the nitrogen in manures of organic origin, which is insoluble and slow in its action, into more soluble and consequently more active forms. It is hence peculiarly applicable to ground bone and fish-guano." He recommends to add about 30 quarts of urine to 100 pounds of bone or guano, and cover the heap with plaster (gypsum) or earth to prevent the escape of ammonia. If this is properly done, the mass will ferment, and the temperature rise to a little above 100° Fahr. The completion of the process, for which three or four weeks should suffice, is indicated by the cooling of the heap. Potassic Fertilizers. The German Potash Salts are assuming a very important place in the list of our commercial fertilizers. Unfortunate ly, the large part of the potash salts brought into this country are of low grades, which contain but little of potassium compounds, and a good deal of common salt and magnesium compounds, which have but little agricultural value, and particularly chloride of magnesium, which may be injurious to crops. The Leopoldshall Kainit, so largely sold in our markets, belongs to this class. This usually contains about 23 per cent. of sulphate of potash, the rest being ballast, on which cost of freight and handling must be paid. It is but little used in Germany. A great part of the product of the mines is said, upon good authority, to be got rid of by exportation to this country. For the evil-a serious one-of importing and using so much of the low-grade potash salts, both sellers and users are responsible. Importers and dealers naturally handle and encourage the sale of the wares on which the margins of the profit are the largest; and being able to get the heaviest percentages on these poor goods, and to dispose of more of them than they could of the better grades, they buy, advertise, recommend, and sell them. A great many farmers say, "Potash salts are potash salts," and take those that can be had at the lowest price, regardless of quality. As long as they will buy low-grade potash salts and other fertilizers because they are "cheap," they must expect to get poor wares at dear rates, and have poor success in using them. The writer believes the following to be the more impor tant conclusions to be drawn from chemical considerations and practical experience concerning the use of German potash salts as fertilizers. They are taken, with some modifications, from the American Agriculturist, Dec., 1877. Details of experiments and analyses upon which they are based (which limited space here excludes) may be found in "Lecture on Potash in Agriculture" and Report of Connecticut Agricultural Experiment Station, in Report of Connecticut Board of Agriculture for 1876. Experience concerning the use of the German potash salts as fertilizers: 1. Potassium, the basis of potash compounds, is indispensable to the growth of all our cultivated plants. It has at least one specific office in the nutrition of the plant-that of aiding in the formation of carbohydrates (starch). It also facilitates particularly the growth of leguminous crops, and through them the assimilation of nitrogen. Without a plentiful supply of potash, in available forms, full crops are impossible. 2. The German potash salts afford at present the cheapest and most available supply of potash for fertilizers. They supply also more or less of magnesia and sulphuric acid, which are essential ingredients of plant-food, and sometimes deficient in our soils, and of sodium and chlorine compounds, which latter, though useful in diffusing the potassium through the soil and rendering other plant-food of the soil available, and hence often beneficial, may in certain cases be harmful. The objectionable chlorine will, after a time, leach down and away where it can do no harm. 3. The higher grades will be, in general, most profitable for use in this country, because they furnish the most potassium with the least admixture of inferior materials, on which costs of freight and handling must be paid. The chlorides (muriates) with 80 to 84 per cent. of chloride of potassium, corresponding to 50 to 52 per cent. actual potash, and the sulphates with 70 to 80 per cent. of sulphate of potash, or from 38 to 44 per cent. actual potash, are to be especially recommended. Where common salt and magnesium compounds are wanted, and kainit can be obtained cheaply enough and applied long enough beforehand, it may be used with profit. 4. For potatoes, sugar-beets, or tobacco, the sulphates are preferable. For other crops, or on wet lands, the chlorides, which are cheaper, are equally good. And if the chlorides are applied long enough before the seed is put in—¿. e., in the fall-for potatoes or beets to be planted in the following spring, the ill effect of their chlorine upon the quality of the crop will probably be prevented. 5. Potash salts have proved especially useful for fodder crops, as grass and rye; for leguminous crops, as clover, beans, pease, and vetches; and for corn, potatoes, roots, tobacco, and fruits. 6. Potash is most apt to be lacking in light, sandy, and calcareous soils; in those consisting largely of vegetable matters, like peat, muck-beds, and moors, where crops that remove a good deal of potash (such as clover, corn, pota toes, turnips, beets, hops, and tobacco) have been repeatedly grown; and where guanos, phosphates, bone, etc., which supply nitrogen, phosphoric acid, and lime, but little or no potash, do not bring as large returns as formerly. 7. In order to secure uniform diffusion through the soil, the potash salts should be applied as long as possible before the crop is sown. It is well to mix with earth, or to compost, before applying, especially if used shortly before sowing the seed, otherwise they may injure the crops. And, in general, potash salts are well adapted for composting with muck, earth, stable-manure, phosphates, fish, and the like. 8. The best results are generally obtained by using potash salts not alone, but with other fertilizers, as superphosphates, guanos, and fish. Mixtures of these with potash salt form "complete" fertilizers. The proper use of potash salts is as adjuncts to other fertilizers. 9. From 200 pounds to 400 or 500 pounds per acre of the higher and 300 to 600 pounds of the lower grades are appropriate quantities. 10. The question of the need of potash in a given soil can be best decided by actual trial. It will be generally advisable to test the question by experiments on a small scale before making large purchases. The Need of Better Information about Fertilizers Among our farmers is a vital one. While they are buying medium and inferior articles at prices which bring the cost of the valuable ingredients up to from 50 to 200 per cent. above what they need pay for better ones, foreigners are coming to this country and buying up the best materials, and carrying them off to be used by European farmers who have learned their value. Fish manures and slaughterhouse refuse, in which nitrogen can be had at 10 to 20 cents per pound, and phosphoric acid at from 4 to 8 cents per pound, are being exported by the thousand tons; while our farmers are paying from 20 to 50 cents per pound for nitrogen, and equally high prices for phosphoric acid in the inferior articles that we keep at home. And when we import potash salts we take the poorest, and leave our transatlantic friends the best. It is bad enough that these precious elements, for lack of which our soils are suffering and our crops falling away, should go out of the country at all. It is too bad that when foreigners come for them they should be allowed to take the best we have, and send us their refuse in return. COMPOSITION OF PLANTS. Fodder Corn and Sweet-Potatoes. Professor S. W. Johnson reports some analyses of sweetpotato and of fodder corn executed under his direction, by Mr. E. H. Jenkins. Except in the larger content of sugar, the composition of the sweet-potato corresponds very closely to that of the common potato. The nutritive values of the two would be nearly equal. The samples of fodder corn contained, on the average, rather more cellulose, and only about one half as much albuminoids and fats as are given in standard European analyses. This difference is doubtless due to the fact that the corn analyzed was much more mature than that commonly employed in Europe. This inferiority in quality of the older corn is probably more than made up by the larger quantity, particularly if it be fed with judicious admixtures of concentrated foods, like cotton-seed cake, linseed cake, bran, or corn-meal, which will supply the deficient albuminoids and fats. (American Journal of Science, xiii., 196). Buckwheat Straw. To determine the composition of the straw as grown on the farm, Professor F. H. Storer has made analyses of two samples which turned out very similar to the straw of wheat, oats, barley, and other cereal grain, both in ash and proximate constituents. "A ton (2000 pounds) would contain about 6 pounds of phosphoric acid, 40 or 50 pounds of real potash, and 12 pounds of nitrogen." As regards the fodder value, Professor Storer says: "It would seem from the analyses that buckwheat straw, when mixed in small proportion with richer kinds of foods, might, like other straws, be usefully employed for feeding animals in many cases; especially if it were previously softened by steaming or soak |