July i, j88j.] 
THE TROPICAL AGRICULTURIST. 
'55 
of this kind be worked through a commercial house, 
of course, of good standing. I could make some ar- 
rangement with the enclosed or any other house, and 
get them to ship a small cargo of suitable nitrate, 
but the enterprise must come from your side, as many 
have been the disappointments here in Shipping to 
markets where the article has lingered unappreciated. 
The plan would be : along with a good house for 
your friends the planters, &c, to get a small cargo 
of say GOO tons taken up between them. 1 believe 
that from a proper application of the material they 
would reap nothing but benefit. It must be adminis- 
tered in the main only as a stimulant. But in a so- 
called unrefined nitrate, which I would prefer to send, 
there would be the advantage of the traces of iodine, 
&c. , &c, which must long have been washed out of 
your upper regions, and which nature might .find some 
subtle use for. 
Rather than send a whole cargo of nitrate of soda, 
I should advise, say, holP, in some phosphatic guano. 
This, mixed with a proportion of nitrate, would make 
an ideal manure, and especially with you, where your 
product drnws heavily on the phosphorus in the soil. 
There is no better form in which to apply phosphoric 
acid than in these guanos. Prom the fine state 
of subdivision, the plant can assimilate as much 
as it lequires and the rest remains. As regards the 
sale of guano, there should be no doubt, if 
the price can be kept at all within the mark, 
as no doubt your owners of land are well aware that 
money so spent is so much on the value of the land, 
for some years to come. 
Save yon any traffic in phosphoric manures in the 
island, by which I can reckon what you are in the 
habit of paying for phosphoric acid ? You ought to 
have some sources of phosphoric acid of your own, 
in the shape of mineral phosphates, or antediluvia 
bones. Are they looked after? 
Sou mentioned felspar asabundaut. If it is orthoclase 
it might have a value for the potash it contains (a 
much as 10 or 12 per cent in a pure specimen. 
That would be supposing you had a cheap water power, 
by which to reduce it to impalpable powder. In 
that stale, with the help of the carbonic acid of the 
air and rain, the plant could extract what potash it 
wanted. Mixed with a little nitrate, it would become, 
still more soluble, and it would be a great addi- 
tion to the value, il ground up with natural phos 
phates. From what I reckon, quartz crushing here, 
the cost of grinding &c, might be 10s. per ton. 
Now-a day*, I observe that fine grinding is being 
feoognized as better than solution in acids for min- 
eral manures. 
How are you oft' for water power ? There should, 
I imagine, be many mountain streams with falls, if not 
abundance of water. With . r i0 ft. fall and upwards, 
a very liti lo water goes a long way. 
Cinchona. — If I get any seed at all, 1 should 
think it would be of the best kind, but it 
would be more satisfactory if luck had taken me, 
or si ill takes me, that way myself. 
Tlio principal cultivator began about six years since 
t.> re-plant in the same ravines in which the trees 
had erst flourished naturally, ami 1 hear with great 
success. He seems to cut down the fifth year's growth, 
replacing accordingly, and the bark gives six to seven 
per cent. 
The property now is supposed to be wortli some 
88(H), 000, but he was mixed up with Daza (ex-president,) 
and now 1 should fancy liis pocuinary prospects are 
clouded. 
There appear to be two varieties cultivated, but my 
impression is that more value there is thought to bo in 
and part of batk selected than in variety. 
I have had to report a good deal lately on gold mine-, 
which are becoming the rage again. They have never 
»s yet done well m Chili as they have been taken up 
with too small a capital. I am glad to see that in 
Southern India they are pitched at a higher scale, and 
with honesty in management ought to pay. 
As soon as things are settled. I suppose 1 shall be 
in Bolivia again to look at some silver mines. My last 
trip north was interesting, as 1 saw a new class of 
nitrate deposit not before understood. 
You will have been glad to read of the success of 
the Chilians in Lima. The army behaved admirably 
after the fight, and reports you may have seen as to 
Chilian excesses are simply untrue. 
Chili is not perfect, but its people are industrious 
and justice is pure, which cannot be said of Peru or 
Bolivia. 
Extracts from the " Field" referred to. 
LIME AND ITS COMPOUNDS. 
The chief forms in which lime is used in agriculture 
are quicklime, carbonate, phosphate, superphosphate, 
and sulphate of lime. I propose to offer some sug- 
gestions on the considerations which should guide 
our choice of the particular form of lime to apply 
according to the circumstances of various cases. The 
carbonate, phosphate, and sulphate are natural pro- 
ductions, but quicklime and superphosphate are manu- 
factured commodities. 
As quicklime is the simplest form, I will deal with 
it first. Beside the name quicklime, it is called hot 
lime, burned lime, caustic lime, &c. ; but the single 
word "lime" exactly represents its composition, and 
and is the best term that can be used for it. This 
lime is manufactured from its carbonate, which exists 
in the form either of limestone or of chalk, and is 
composed of 56 parts of lime and 44 parts of carbon- 
ic acid, making 100 parts by weight of carbonate. 
By heating in kilns the whole of the carbonic acid 
is driven off, and lime is left. By this treatment, 
the lime having lost its neutralising acid, has become 
a highly active substance, exhibiting great caustic 
properties, and energetically endeavouring to unite 
with some other body capable of satisfying and neu- 
tralising its peculiarly active Character. This craving 
is usually satisfied in the 'lowing manner. Water 
may be added, or if not, i. ! lime will get it from 
the atmosphere, when combination takes place. In 
the former case it is quickly accomplished, and great 
heat is consequently developed ; whilst in the latter 
a slow union goes on, proporiiouately as the lime can 
obtain the moisture from the surrounding air. When 
the reaction is complete, hydrate of lime has been 
formed, and its composition is by weight as follows: 
Lime, 56 parts ; water, 18 parts. This hydrate 
is a dry whitish powder, and is soluble in water, 
which fact is highly important, as it will be seen that 
the next change reuders it a body perfectly insoluble 
in that medium when pure. Now the carbonic acid in 
the air begins to act on the hydrate, and gradually but 
completely turns out the water, and in course of time 
regains its original position of union with the lime, so 
that now we have the same compound that we started 
with, viz., carbonate of lime; and the only difference 
is that now it is in a minutely divided state, and so 
can the better be acted upon by disintegrating 
agencies, but otherwise it is quite as insoluble as the 
chalk was in the first place. Therefore, to furnish 
plant food for present use, the lime should be applied 
before it has taken back its carbonic acid from (he 
atmosphere. 
Now, these various changes must be clearly under- 
stood if we are to know when and how to apply lime to 
the soil to tho greatest advantage to the land and our- 
selves. When the lime is in the soil — suppose, for iu- 
I stance, in its form of hydrate — instead of getting sup- 
plied with carbonic acid from the air, it gets it from 
decomposing matter in the soil, and by so carrying 
off the products of decomposition, aids and hastens the. 
