17 
more noticeable in what would have been the most fertile land in 
the field, in hollows, or at the base of sloping ground, where these 
salts accumulate. 
SaLt PatcHEs 
Two sorts of salt patches occur in the drier regions of the State: 
the “white” patches caused by formation of crust or efflorescences on 
the surface of the soil of salts, which present the appearance of 
hoar frost on the ground. These salts mostly consist of common 
salt (chloride of sodium), with chlorides and sulphates of calcium 
and magnesium. Unless present in large quantities, these salts are 
comparatively harmless. 
The second, the “black” salt patches, are more injurious to veve- 
tation, and in addition to common salt contain Glauber’s salt (sul- 
phate of soda), and with it a varying amount of a substance mest 
destructive to vegetable tissues, viz., carbonate of soda or sal. 
soda. The presence of this salt is always indieated by the colour of 
the soil in the black salt patches. The latter salt has, on the tissues 
of plants, a corrosive action; it- dissolves the humus contained in 
the soil, and thus gives it the characteristic black colour often 
noticeable in such patches. The presence of this chemical salt in 
the soils is, even in small quantities, detrimental to the growth of 
roots of the plant, whereas the salts found in the white patches are 
only injurious when their accumulation becomes excessive, especially 
at the surface. 
The reclamation of salt patches for the purpose cf bringing 
them under cultivation rests upon three chief points :— 
1. Draining to carry away the excess salt and preventing 
fresh amounts being drawn up from the subsoil below. This 
is the one efficacious and radical way of reclaiming salt 
patches of any sort. The underdrainage in deep hollows is 
not only often impracticable but is generally costly. Be- 
sides, there is often found, in conjunction with these 
noxious salts, other chemicals of high fertilising value, such 
as sulphates, nitrates, phosphates of potash and soda, which 
would run away to waste in the drains and be lost to the 
soil. Should this be the ease, it would in many instances be 
advisable to alter the poisonous substances in the soil and 
neutralise their injurious effect, so as to place them beyond 
the means of causing any injury, and this can be effected 
by— 
2. Neutralising the corrosive salts by means of chemicals and 
changing their nature into that of the more innocuous ones. 
To best effect this, some cheap substance, which by chemi- 
a 
