238 PERUVIAN GUANO, ETC. [chap. 



years been a favourite manure among hop growers ; 

 it is also occasionally used for root crops when farm- 

 yard manure is not available. It should be applied 

 early in the year, when the land is first worked, and 

 it should be dug or ploughed into the land as soon as 

 sown, otherwise rooks and other birds will eat it as 

 long as they are allowed to do so. Like all manures 

 of this class, it is injurious to germinating seeds or the 

 tender rootlets of growing plants, until it has been in 

 the soil for a short time and the first active fermenta- 

 tion is over. 



Meat guano is prepared from all kinds of slaughter- 

 house refuse in much the same way as fish guano — the 

 waste of carcases, condemned imported meat, tallow 

 boilers refuse, the residues obtained in making meat 

 extracts, and so forth, are heated and pressed to 

 remove fat, and the residue is then finely ground. 

 Material of this class, though more often after treatment 

 with acid or other admixture, is known in America 

 as " tankage." In some cases a good deal of bone is 

 mixed with the material before grinding, and the 

 resulting " guano " approximates to bone meal ; in other 

 cases the nitrogenous material predominates. Thus 

 the nitrogen may be as high as 12-13 per cent., in 

 which case there is little or no phosphate of lime 

 present; whereas at the other end of the scale come 

 mixtures with 4 to 5 per cent, of nitrogen and 35 to 40 

 per cent, of phosphate of lime. A good representative 

 example, manufactured by the Liebeg Company under 

 the name of Fray Bentos Guano, contained 7 per cent, 

 of nitrogen and 30 per cent, of phosphate of lime, all 

 in a fine friable condition, dry, and suitable for sowing. 



In its action and uses meat is very similar to fish 

 guano, and all that has been said about the time and 

 manner of application of the one, equally applies to 



