3G8 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



vancc lias been taken by Messrs. Ilobson, Ilurtado, 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 ammo- 

 niated 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 Sta- 

 tion 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 excel- 

 lent means for transforming: the nitrogen in manures of or^an- 

 ic origin, which is insoluble and slow in its action, into more 

 soluble and consequently more active forms. It is hence pe- 

 culiarly applicable to ground bone and fish-guano." He recom- 

 mends to add about 30 quarts of urine to 100 pounds of bono 

 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- 



