January i, 1890,] THE TROPICAL 
AGRICULTURIST. 
473 
VINE PESTS. 
The following extract is taken from Nature, of 
August 15th. The Agricultural Society of the Grironde, 
as quoted in a recent British Consular report, has 
published a statement shewing the average costs in- 
curred last year by proprietors in this department in 
employing the best-known remedies, viz., (1) against 
the Phylloxera, sulphuretted carbon ; (2) against mildew, 
the so-called Bouillie Bodelaise, a mixture of three 
pounds of sulphate of copper with one pound of 
slaked lime and twenty-two gallons of water ; (3) 
against Oidium, sulphur; and (4) against Antrachnosis, 
a mixture of eighty pounds of sulphate of iron and 
10 pounds of sulphate of copper. The total cost of 
using all these remedies is said to have amounted on 
an average to about 31s. per acre, an expense which 
cannot be called excessive, especially when it is added 
that their application served at the same time as a 
preventive against snails and slugs, which also often 
do much damage to vines. — British North Borneo 
Herald. 
A FEW WORDS ABOUT OIL ENGINES. 
To the Editor, 
Sir, — I notice an article in your Thursday night's 
issue on the subject of oil engines. I saw Messrs. 
Priestly's Engine in London. It is nothing more or less 
than an ordinary gas engine, and the system on which 
it works is identical. The only difference is that you 
heat the oil until it gives forth a gas instead of 
drawing the gas ready made from the main. 
The disadvantage of all gas engines, including 
Messrs. Priestly's oil engine, is that they can in the 
first place only be run at one speed, and secondly that 
they only give out the nominal horse-power and no 
more. For instance, a ten horse-power steam engine 
will easily produce fifteen to seventeen horse-power. 
A ten horse-power gas engine, however, will only pro- 
duce ten horse, as a general rule a good deal under, 
unless all the valves are specially clean and the pres- 
sure of gas a good one. Practically, therefore, to 
work a gas engine you want one of about double 
the nominal power of the steam engine you already 
have in your factory. This is the more necessary as 
in the ordinary patterns, such as the " Otto," the 
explosion occurs only every second revolution, and 
any sudden strain is therefore more likely to put 
the machine out of gear. 
"With regard to the speed, there is one make (Messrs. 
Atkinson Sons' patent) where the speed can be varied 
at will, and in which the explosion occurs at every re- 
volution. There is also a method of manufacturing 
gas to use with this machine where none is available 
in the ordinary way. The chief point, however, as 
regards the utility of the machines for tea factories is 
the cost. A 20-horse gas would cost between two to 
three times as much as a 10-horse steam-engine with 
a 12-horse boiler. What we really require is some 
system of using oil to heat an oridnary steam boiler, 
and I believe that experiments are being carried on 
in this direction. 
If a method is discovered, it would be applicable to 
heating Siroccos and other firing machines as well as 
boilers, and one difficulty as regards the future of 
Dimbulla and adjoining districts would be solved. 
MACHINIST. 
Colombo, December 13th. 
— Local " Times." 

THE QUALITY OF COCONUT OIL. 
Manufacturers of Ceylon coconut oil are making an 
investigation at this late day of the comparative quality 
of the two grades of coconut oil which are made in 
Ceylon and Cochin, with the view of ascertaining why 
the latter is considered superior and commands a 
higher price than its rival. The parties makiug the 
inquiry had previously arrived at the conclusion that 
the difference in quality was due to the soil of the 
two localities where the coconut trees are cultivated, 
but a geologist made it appear that such a theory was 
absurd and they directed attention to the methods 
60 
employed in drying the nuts. We see it announced 
that the difference in quality is now attributed to the 
fact that the whole fruit is subjected to artificial heat 
for three months in Cochin, while iu Ceylon the nuts 
are split in half and sun dried. Dealers in the article 
on the other side claim that Cochin oil is richer in 
stearine, while operators in Ceylon oil exclusively are 
disposed to question the legitimacy of the distinction 
which they think is partly due to commercial " jugglery." 
In this market the credit is given to an improved 
process of manufacture, but if that were the true 
cause of the superior quality of Cochin oil, there would 
be no excuse for the low grade of coconut oil made in 
England and on the Pacific coast where the manu- 
facturers enjoy much better facilities for their business 
and are in a position to learn the latest improvements 
before they they are introduced in the far East. How- 
ever, the last argument has been demonstrated as a 
fact by practical experience. The finest coconut oil 
ever seen in any market has been made in this State 
from refuse material in desiccated cocouut factories, 
by a process not known outside of the United States, 
and if the coconut growing countries were nearer home, 
there would be no necessity for importing the oils. 
Owing to the cost of transporting the nuts, the 
American oil industry can never reach large propor- 
tions, as it is confined to the utilization of a by-product. 
If the Ceylon people would carry out their experi- 
ments in the direction of employing an improved 
process in manufacturing, they may be successful in 
meeting competition both in quality and price. They 
will have to depart from old-time customs and commu- 
nicate with the new world in regard to the latest 
contrivances, instead of relying so much on " coolie " 
labor to accomplish the desired results. — Oil, Paint and 
Drug Reporter. 
♦ 
A NEW SHADE TREE FOR CACAO. 
The extensive injury done to the Bois Immortel in 
the Oacasjuals of the mainland by locusts about three 
years ago compelled the planters to seek for a shade- 
tree that would not be exposed to their ravages. The 
Cacagueros of the district behind Yrapa have discovered 
in the Apamato, a native tree of the neighbouring 
forests, one which they think to be better for their 
purpose in many ways than the time-honoured 
Erythrinas. Its wood is stronger, in stem and branch ; 
the foliage is thicker, and the long and darker leaf is 
persistent, not dropping from the tree in the dry 
season, thus protecting the Cacao trees throughout 
the year ; and the branches, which are not formed 
or do not spread widely till the tree has shot up to 
a considerable height, are stiff and not liable to be 
broken by high winds. Locusts do not attack this class 
of leaf. Specimens of the young plant have been sent 
for, to the Main, by my informant, Mr. Pedro 
Ducharme, of this town, aa well as, if procurable just 
now, the flower aud fruit or seed, in order to trace 
its botanical affinities. 
The tree is said to attain about the same bulk of 
stem and height as the B. Immortel, with a spread at 
top of about 45 or 50 feet. The Oacao-planters of the 
Yrapa district are replacing their Anaucos and Bucares 
by the new tree as fast as they can. 
Stronger, closer fibre indicates slower growth, and it 
seems likely that even if the Apamato when full-grown 
offers a shade better for Cacao than the Immortel, it 
mustbe supplemented in young plantations by a more 
rapidly-growing tree till the new plant, having shot 
up and made its spreading head, the temporary and 
provisional shall be removed. 
As Mr. Ducharme does rot speak from personal 
experience lor knowledge of the Apamato, aud so many 
proposed alternatives for the old madre del cacao have 
failed to dethroneher, it is as well to reserve opinions 
till more exact information be received. The thanks 
of Cacao-growers are meanwhile due to Mr. Ducharme 
for what may prove to be a hint of some value to them. 
8th August, 1889. T. W. 0. 
P.S. — Later in the day I met a friend from Maturin, 
who, on being asked, said the tree was well known to 
him. According to him, it is a very tall tree, branching 
