24 



AGRICULTURE AND FORESTRY. 



I per cent, organic matter. Kinch very properly points to the 

 remarkably large proportion (40 per cent.) of easily broken 

 silicates {i.e. the above-mentioned zeoliths), and the almost total 

 absence of free silicic acid. Its richness in magnetic iron, to which, 

 besides organic matter, this tufa-soil owes its dark-brown colour, 

 was approximately calculated by Kinch with a magnet, and loam 

 from Komaba gave 2*5 per cent, in one test, and some from Shi- 

 mosa even 7 per cent, of the total weight. The soil of Japan has 

 great capacity for absorption and for holding water ; but being deep 

 and porous, it suffers little from sagginess, even after heavy rains. 



The predominance of acid silicates, including trachytic tufa and 

 ashes, — of which the best loam in Japan is largely composed, — 

 explains its extraordinary poverty in elements most necessary for 

 plant-food : lime, potash, and phosphoric acid ; and this poverty 

 increases from the surface downward, as manures tend to make the 

 top-layers more fertile. Kinch determines as follows the average 

 content, from six tests, after deduction of the hygroscopic water : 



Phosphoric acid, 0*185 per cent. ; potash, 0*363 per cent. ; lime, 

 0*475 per cent. 



The results of his investigations, and those of Korschelt, were 

 confirmed and considerably extended a year ago by the analyses 

 of Kellner. Two of these follow here, taken from the work already 

 cited, in Nobbe's " Landwirthschaftliche Versuchs-stationen," vol. 

 XXX. The specimens of earth, like those which Kinch examined, 

 were taken from the Kuwanto. 



The earth was dried at 100° C, and then, by means of cold 

 muriatic acid of 1*15 specific weight, were extracted the following : 



