April i, 1889] THE TROPICAL AGRICULTURIST. 
6ji 
After this the correspondence ceased. In a letter, 
however, which appeared in the Madras Mail of the 
26th April last, signed " Novice," the subject is again 
alluded to. In that letter the writer states that an 
artificial freezing chamber to provide the requisite 
low temperature for the extraction of the bye-pro- 
ducts could be cheaply and profitably set up in India, 
and that a few years ago he had some correspondence 
wioh the Salt Department with reference to the use 
of "bitterns" for agricultural purposes but that alter 
the matter had been handed over to the Assistant 
Commissioner of the Central Division he heard no 
more of it. The Commissioner of Separate Revenue 
will be asked whether he can favor the Board with 
any further information on the points alluded to 
above, viz. — 
(1) Whether Mr. McKenzie actually obtained any 
"bitterns'' in 1885 for experimental use as manure. 
(2) Whether the extraction of the bye-products 
from bitterns is as feasible as the correspendent of 
the Mail seems to think it is. 
Mr. Benson's suggestion of mixing the " bitterns " 
with manure heaps is, like those of Mr. Bliss, good 
and practical. Diffused in large masses of manure, 
the chemical substances would be useful and not 
harmful. The Wynaad Planters' Association decided 
in Oct. 1888 that 
Bitterns would lie of no practical value for any 
of the products in Wynaad. 
Major-General Morgan, on behalf of the Nilgiri 
Miners' and Planters' Association, made suph safe 
general st dements as these : — 
Speaking generally, the use of bitterns, when mixed 
with farm-yard manure, would be decidedly efficacious 
in killing grubs and in strengthening the straw of 
grain crops, especially if mixed with quicklime and 
used in inland districts. 
It is difficult to point out its special use unless the 
price at the salt depots is known. If quicklime is 
mixed with the bitterns, sulphate of lime is produced, 
which is very valuable for agriculture. 
Mr. MacNab, Chairman of the Chamber of Com- 
merce of Coconada, stated that 
In the opinion of this Chamber, bitterns, as such, 
could serve no useful purpose as manure; on the con- 
trary, it is cpusidered that they would be injurious, 
if not fatal, to auy form of plant life, while the cost 
of carriage would be prohibitive. Of the ingredients 
of the mother liquor, as already pointed out in these 
Proceedings, gypsum is readily obtainable from other 
sources, while magnesium sulphate is valueless ; and 
as regards the potassium salts, which are alone of 
substantial value, it is feared that the expense of 
refrigeration in this country, combined with 
the uncertainty of success and of finding a 
market even if the salts were successfully 
evolved, would probably deter any private firm or in- 
dividual from undertaking the experiment. The im- 
provements yearly being made in refrigerating appa- 
ratus may materially modify the risk involved, and 
there can be no question of the economic value to the 
leaf crops of the country of a cheap form of potash 
for use as manure. It appears to the Chamber, how- 
ever, to be very doubtful, whether, potassium salts 
obtained by artificial refrigeration in the intense heat 
of an Indian salterue in the manufacturing season 
could compete with the imported article manufactured 
in the natural winter cold of Europe. I am however 
placing the papers before Messrs. Hall, Wilson and 
Co., who are already interested in salt manufacture, 
and I shall ask them to address you in the matter, 
if they find themselves able to offer any contribution 
to your consideration of the subject. 
The Firm referred to accordingly wrote : — 
We have been engaged in the manufacture of salt 
(at Karassa near Vizagapatam) for the past six years, 
and from time to time we have had under considera- 
tion the feasibility of securing the residual salts con- 
tained in tho mothor liquor, which at present runs 
to waste. Of these, the only ingredients of appre- 
ciable commercial valno are the potassium salts, and 
wo liavo hitherto boeu doterred from attempting to 
rescue them by the condition of artificial refrigera- 
tion, which is necessary to their extraction. Re- 
frigerating apparatus is costly, and in our experience 
it is always (except when applied on a large scale 
under skilled European supervision) very uncertain 
in operation in this country. There is al6o a consi 
derable element of doubt as to whether we could find 
a market at paying prices for our potassium chloride, 
even if we were successful in extracting it, and on 
that point we can form no definite opinion until we 
know the cost of production, which can only be as- 
certained in actual working. 
We have now before Government, however, an ap- 
plication to be allowed to lay out a new salt factory 
here at Oocanada immediately adjoining our own premi"- 
ses, and, if this is granted to us, our intention is to 
irrigate by steam -pumping machinery. We should 
thus have on the spot the steam power, which, next 
perhaps to skilled supervision, is the most expensive 
item in the cost of refrigerating in India, and we 
should have the inestimable advantage of conducting 
under our own immediate eye experiments which we 
should not think of attempting on other conditions. 
Amongst other experiments which we had already had 
in contemplation was the extraction of these residual 
salts, and we are now in correspondence with manu- 
facturers of refrigerators in Europe with a view to 
finding an economic but efficient apparatus, which 
would fulfil the requirements necessary to give the 
thing a fair trial. We have yet to learn, however, 
whether our proposal will receive the sanction of Gov- 
ernment, and we are of course unwilliug to commit 
ourselves to the experiment, until we see clearly 
what the cost will be. If that, however, should promise 
to be moderate, we should be fully disposed to give the 
extraction of these residual salts a fair and exhaustive 
trial, and in that case we need not say we shall most 
gladly gipe you in the fullest possible form the results 
of our experiment. We will merely acid here that 
there seems to us to be a degree of fitness in selecting 
Oocanada for the extraction of these residual salts, 
in that it already produces so largely, probably the 
best manure in India, castor-seed poonac, combination 
of which with potassium chloride might give a resultant 
manure of great value to such of the higher classes 
of agriculture (tea, coffee, sugar, tobacco, &c.) as could 
bear the cost. 
Mr. Lechler, Hon. Secretary, Shevaroy Planters' 
Association, wrote : — 
The Shevaroy Planters' Association are much interested 
in the subject of the use of bitterns for agricultural 
purposes. No experiments appear to have been at- 
tempted with bitterns as manure for coffee, and the 
association are anxious to give them a trial if a small 
quantity can be secured, so as to place the ^matter 
beyond doubt. With this object in view, I write to 
ask you to be so good as to obtain for me a small 
quantity, say 2 cwt., packed in 56 lb. bags, for distribu- 
tion to members of the association, who have guaran- 
teed to make experiments and report results. 
Messrs. Binny & Co. wrote : — 
Referring to memorandum, dated the 20th November 
1888, requesting a report on the use of bitterns for 
agricultural purposes, we have the honor to state that 
the manager of our coffee works writes as follows : — 
'' With reference to the Board of Revenue's memo- 
randum, dated 20th ultimo, which I return under separ- 
ate cover with the accompanying copies of proceedings, 
I now beg to inform you that I have made inquiry 
regarding the use of bitterns as a manure for ooffee ; 
but I cannot suggest any means of employing same. 
I assume that that the bitterns could only be conden- 
sed into gypsum and magnesium sulphate at a com- 
paratively costly expense, and as these salts are only 
occasionally asked for by planters, I do not think it 
would be worth while to undertake any experiments in 
producing them from the bitterns." 
We have nothing to add to the above, and would 
suggest that an opinion be taken of the ' Chemical 
Analyst sent out by Messrs. Matheson & Oo. to their 
estates in Mercara. His address is c/o E. flleynell, 
Esq. As, however, the papers have already boeu 
