384 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



chloride of ammonium and phosphate of ammonia to a con- 

 siderable extent, while the anhydrous double silicates, which 

 are not decomposed by hydrochloric acid, do not absorb the 

 ammonia, but those that are so decomposed do to some ex- 

 tent. By treatment with hydrate of lime these silicates 

 take up water, and are rendered absorbent of ammonia, or, 

 if so before, their absorbing power is increased. Carbonate 

 of lime absorbs but little ammonia from a solution of chlo- 

 ride of ammonium, but somewhat more from a solution of 

 the phosphate. Hamate of lime and peat take out a consid- 

 erable amount of ammonia and potash from solutions of 

 their chlorides, with the passage of an equivalent amount of 

 lime into the solution. Pure humic acid and j)eat, treated 

 with hydrochloric acid, take up less ammonia and potash, 

 under similar conditions. The chlorine in the preceding 

 cases is not absorbed, but remains in the solution, in some 

 cases combined with calcium in part, and in other cases in 

 part as free hydrochloric acid. Phosphoric acid is largely 

 absorbed from a solution of phosphate of ammonia by cha- 

 bazite and stilbite, and also to a great extent by chalk, but 

 the addition of the latter to the chabazite does not increase 

 its absorptive power for phosphoric acid or ammonia. From 

 a solution of a superphosphate the phosphoric acid is taken 

 up very rapidly by humate of lime, and less rapidly, but 

 completely, by acid carbonate of lime and chalk. Other 

 bodies, as stilbite, brown hematite, kaolin, and humic acid, 

 appear to absorb but little or no phosphoric acid from so- 

 lutions of superphosphates. 14 (7, CCXVI., 1875, 92. 



FISH-GUANO, PARTICULARLY THE FATLESS, DRIED, SO-CALLED 



POLAR FISH-GUANO. 



According to Dr. Vohl, large quantities of a small species 

 of herring, so-called sprats (Chtpea sp?'attns), collected upon 

 the coast of England, and crushed, have been employed as 

 manure for wheat and hops with good results. A process 

 was also patented in England in 1854, by Pettitt, for the 

 preparation of an artificial guano from herring by means of 

 sulphuric acid. Analyses of three samples of this guano 

 gave 4.1 per cent., 23.2 per cent., and 3.5 per cent, of phos- 

 phates of the alkaline earths; and 13.8 per cent., 10.6 per 

 cent., and 11.2 per cent, of nitrogen, respectively. This in- 



