8 
Garden Work 
added to supply the deficiency of inorganic matter. There 
are two great classes of peat soils: (a) black peat, which, 
when treated as above, produces excellent crops of most 
vegetables, but especially of potatoes and carrots; ( b ) 
brown peat, which will not readily respond to any known 
treatment. This peat has been formed in stagnant bogs 
where the vegetable acids, not being able to drain away, 
have got fixed into the peat itself. On the other hand, 
black peat has been formed in bogs where the acids of 
decaying vegetation have drained away naturally, leaving 
a rich and fertile soil. 
F. CALCAREOUS SOILS 
Such soils have over 20 per cent of lime in them. 
They may be either loamy, sandy, or more or less stiff 
clay. The fertility of these soils depends upon the 
amount of sand, loam, or clay they contain. The colour 
of soils has some effect on the crops grown on them. A 
dark soil absorbs the heat, while a light soil radiates it. 
When a light soil is once heated it retains its heat longer 
than a dark soil. The colour of soils also has a different 
effect on the amount of ammonia they can absorb from 
the atmosphere. This, however, is beyond the scope of 
the present book. 
THE CULTIVATION OF SOILS 
Stiff clay soils should be trenched in autumn, if the 
depth of soil will allow it to be done, and left in a rough 
condition, so that as large a surface as possible may be 
exposed to the action of the frost, &c. The water becomes 
