THE 
Vol. VIII. I 
COLOMBO, APRIL ist, 1889. 
[No. 10. 
SALTPANS RESIDUUM, SALT AND ITS 
BY-PRODUCTS AS MANURES. 
XCEPT in the case of coconuts 
and that not to any large 
extent, the manurial value o£ 
salt and its by-products is 
not, we believe high. Salt is 
no doubt good for killing 
white-ants and weeds, and its 
associated products in " bitterns "—Glauber's salts 
or the sulphate of soda and Epsom salts 
or the sulphate of magnesia, especially the 
latter, — may be good as antidotes to fungi. 
But we question whether the fertilizing 
properties of salt are so great as some imagine. 
The late Mr. David Wilson raised the whole 
question, and the subsidiary one of denaturalizing 
salt (in the- interests of the monopoly revenue 
which cannot be dispensed with) was settled in 
the negative, the late Dr. Charsley showing, that, 
even when adulterated with nightsoil, salt 
could be restored in pure clean crystals 
by the use of charcoal. If salt is of real 
manurial value, we repeat what we said once 
before, that it exists largely in kainit, which, is, 
admitted free here as a manure. The potash which 
is associated with common salt in this mineral 
is undoubtedly beneficial to tea, so that, if kainit 
could be obtained at a moderate price, it would 
meet the wants of those who believe in the 
valuable manurial qualities of chloride of sodium. 
That "salt is good" we know on the highest 
authority, but its valuable properties as a component 
in the food of man and animals do not seem 
to be so apparent in the promotion of vegetable 
life. On the other hand salt can be seriously 
injurious and even fatal to vegetable life, During the 
specially inclement south-west monsoon of 1882, 
we had proof, as we ventured to assert 
at the time and still believe, of the mischief 
which salt in excess in the atmosphere can 
work on vegetation. No one can doubt that 
on the wings of the monsoon winds, and in the 
globules of moisture with which thoy are laden, 
some portions of saline mattor captured from the 
ocean spray are diffused. In such ordinary 
proportion the presence of the great antiseptic 
and purifying substance is valuable. But like 
other good things, such as fire and water and 
oven the blessed sunshine, salt in excess is capable 
of becoming a curse instead of a blessing. The re- 
cords of meteorology contain accounts of salt 
storms which have inflicted great injury on vegeta- 
tion, in some cases fatal injury on orchard and 
forest trees. The stems and limbs of trees ex- 
posed to this destructive agency have swelled and 
festered after the fashion of a diseased human 
limb. With these facts within our knowledge, we 
did not hesitate to express the conviction that in 
the course of the specially inclement south-west 
monsoon of 1882, when it seemed as if the wind 
and rain increased in force and quantity day by 
day, salt storms reached and affected vegetation 
growing on the higher mountain regions of the 
island. We did not hear of any special effect on 
coffee in addition to the effects of the chronic 
fungous disease, and tea did not suffer much, al- 
though the smallpox-like spots which marked 
the leaves of such exotics as cinchona and the 
eucalypti created alarm by spreading in some cases 
to the tea leaves. But it was on the tall, un- 
protected stems of the Australian " gum " trees, 
especially the blue gum, that the storms carrying 
excess of saline matter, we believe, when specially 
violent and long-continued, told with chief viru- 
lence. The stems, at various altitudes, swelled 
and bulged out, tbe skin cracked and blackened, 
the portions of the trees above the swelled part 
put on a sickly appearance, or died, and there 
was an instinctive attempt at renewed existence 
in the shape of the curious primitive foliage com- 
ing out below the diseased part. 
Mr. J. Mackenzie, a Nilgiri planter, who is a subscri- 
ber to the Tropical Agriculturist, had seen this theory 
of ours, and seems to have arrived at the conclusion 
that what was evil in excess must be specially bene- 
ficial in moderation. Accordingly we are in pos- 
session, almost simultaneously, of the opinion 
of a former Haputale planter that exposure to sea 
breezes is likely to prevent the success of tea in the 
more eastern portions of Uva and of Mr. Mackenzie's ■ 
opinion, imparted to the Madras Government, that 
the superiority of the Ceylon tea, which he admits, 
is due to the presence of salt diffused in our at- 
mosphere. He, therefore, suggests that the residuary 
matter in salt " bitterns " would be a valuable 
application to tea in the Madras Presidency. This 
suggestion, which Mr. Mackenzie seems to have 
taken no step to carry practically into effect, al- 
though he was offered the chance, led to a most 
interesting correspondence, which has reached ua 
from the Madras Government. Mr. Bliss, the 
very able Commissioner of Salt Revenue, on 
