SOILS AND MANURES. 207 
s deleterious, and Mr. Hughes states the proposition 
that generally the iron and alumina in a soil should 
not, united, exceed 15 to 18 per cent ; but he makes an 
exception in favour of peroxide of iron, the source of 
the red colour of very fertile soils. This form of iron 
combines with phosphoric acid,and is valuable as a fixer 
of ammonia, and Mr. Hughes mentions the case of 
a Ceylon soil of excellent quality, though ferruginous 
to more than twice the extent deemed generally 
desirable. We need scarcely remind our readers that 
soils containinga good deal ofiron are specially fitted 
for the growth of the tea plant. The value of peroxide 
of iron in fixing ammonia is worthy of attention ; but Mr. 
Hughes adheres to the conviction that, as a general rule, 
the soils of the coffee districts, especially of the young 
districts, do not so much need direct applications of 
nitrogen or salts of potash, as their indirect applica- 
tion in the shape of oil-cakes (especially white castor- 
cake), and high class superphosphate and bones. Mr. 
Hughes still insists, too, on the value of lime, forked 
into the surface soil. He does not belong to the 
school of ‘‘ Medico-Agri-Horticulturists” whose panacea 
for all ills is the reversal of the positions of mellow 
soil (down to 12 or 18 imehes from the surface), and 
sour, inert sub-soil: sending the one down to feed the 
taproots, and the other up to starve the feeding rootlets. 
For the vast majority of the soils of Ceylon, Mr. 
Hughes recommended and still recommends, not an 
impossible and deleterious, if possible, bringing of 
the subsoil to the surface, but the improvement of 
the mechanical condition of the surface soil by fork- 
ing lime into it to the depth of 12 or 15 inches, at 
the rate of one-fourth to one-half ton per acre, foliow- 
ing this up with cake containing nitrogen and potash 
besides valuable mineral constituents, and with bones 
and superphosphate, at rates varying with the condition 
of the soil as indicated by analysis. While he recom- 
mends the digging of the soil (not the subsoil) he re- 
commends drainage and, where possible, terracing for 
the retention of soil exposed to wash. 
The following is of almost general application, only 
that where nitrogen is abundant the cake may be 
omitted :— 
“lf cattle manure is available, the most economical 
dressing will be a basket of dung and #4 |b. of slaked 
lime per tree ; otherwise, a mixture of— 
Per tree. 
i lb. steamed bones (Leechman’s). 
3 lb. rape or castor poonac (finely ground). 
+ 1b. high-class superphosphate, 44 per cent of 
soluble phosphate (Lawes’). 
