68 
Su2:)plement to the Tropical AgricuUiorist." [July i, i902i 
Method of A pphcat'wii. — For applying llie solu- 
tion a ]ioWerful " Doiicastev" spray plirop wns 
iisecl. This xvas mounted on an 80 gal. vat and 
placed in a light cart drawn Ly a single horse. 
Two lengths cf hose were attached and 
connected with nozzle? monnted on light iron 
pipes, so that two sprays were working at once; 
and by means of the pipes the sprny could be got 
over the top of the tallest plants. It takes one 
man and two boys (or three boys would do) to 
carry out the work, i.d one to work the pump 
and drive the horse, and two to apply the sprayj 
With this plant there is no difficulty in spraying 
an acre of thickly-infested pear land per day, 
and, generally, asthe land is rarely thickly covered, 
some few acies per day could be fprayed. 
Time to a^ipli/.-^The experiments extended over 
two years, and as they were conducted at regular 
iutervals, a good opinion could be formed as to 
the best time to spray. It appears that, as might 
be expected, the spray proved most effective when 
the sap was active, i.e., in spring or summer after 
heavy rains. 
C'ok.— It was estimated that to spray an acre 
of land thickly covered would cost as follows : — 
80 lb. solium arsenite, at 3id. 0 18 8 
Application — wages for 1 man 
and 2 boys 0 12 0 
Horse and cart for 1 day ... 0 6 0 
As a rule, however, even on badly-infested 
land, 1 do not think that the cost of spraying 
would exceed 10s. or 15s. per acre, and often it 
could be done for less. 
Sodium arsenite can be purchased in Sydney 
atSgff. per lb. for large quantities. 
Spray pumps suitable for the pui-pose can be 
obtained at from about £4 to £10 each, complete. 
Almost any ordinary spray pump will do, such 
as those used by the fruit-growers. 
IJffect of the Sprai/. — The action of the spray 
was very rapid, as within 24 hours the leaves 
were fading, and a strong smell of decaying 
vegetation was given off. By the end of the 
first week the foliage hnd all turned brown, 
and large numbers of the leaves had broken off 
and fallen to the ground. Within from three xoeeks 
to a month ike foliage had decayed, and was 
sufficiently dry to burn off raindly without the 
aid of brmkwood, ^-c. 
In all cases it was found that none of the 
chemicals destroyed the roots of the pears, and 
nearly all the plants made a fresh growth if left 
undisturbed. If, however, the decayed mass is 
burned off, there is very little trouble from plants 
shooting again ; and should they show any signs 
of life,' the few roots that do start can be easily 
removed, as they are only very shallow. 
Danrjer to stock. — In using any poisonous spray 
for eradicating prickly pears, &c„ there is a great 
risk of stock being killed if they are allowed to 
graze in the i)addock where the treatment is 
being applied, No matter how carefully the 
spraying is carried out, the grass near the plants 
is certiiin to receive some of the poison, and 
should stock eat this they may die. If, however, 
the stock are kept out of the paddock for a week 
or so, there is little danger aiterwards as the 
poisou soou disappears, 
Briars, lantana thistles, and other weeds can 
be treated in a similar way to the pears, and i 
will be found that the arsenite of soda solution 
is very effective in destroying them. Also it is 
a good )emedy for eradicating couch grass from 
garden paths, roads, &c. 
COCOA ANl) ITS ADULTEKATION. 
[by an EXPEKt.] 
Theohrovia, meaiiing in the Greek ''the food of 
the gods " was the name given to cocoa by the 
eminent botanist, Linnaeus, who could find no 
language more fit to express the inestimable 
qualities and the delicious flavour of this food. 
In Mexico, in the untrodden mould of forests 
primreval, by the banks of the mighty Amiizon, 
and hidden away under the cojl sh.ade of the 
heavily-timbered glens and ravines, may still be 
seen this rare and beautiful plant in all its wild 
luxuiiance. 
In many parts of the world it is, however, now 
found under cultivation. 
" Historicus " writing on cocoa so lately ns 
1892, says that the finest qualities are grown in 
Central America, Trinidad and Ceylon. "The 
latter is of comparatively recent cultivation, but 
it is the most delicate in colour, flavour and 
aroma, and unfrequently commands the highest 
value in the market." 
Ferguson in his Ceylon in 1834 says : '• To the 
late E. B. Tytler belongs the credit of introducing 
tills cultivation, and in his hands Ceylon cocoa 
speedily lealized the highest piices in the London 
market, experienced brokers remiirking that 
there must be something in the soil and climate 
of Ceylon peculiarly suited to cocoa." That is so. 
Our earliest acquaintance with cocoa as an article 
of diet may be dated from 1494, in connection 
with the discovery of the western world by 
Columbus; but its great value was known long 
before to the dwellers of the countries where the 
plant grew. 
Frescott, in his history of the conquest of Peru, 
says: "The Emperor icok no other beverage 
than the chocolate. The beverage, if so it can be 
called, was served in golden goblets." 
So early as in the reign of Charles II. medical 
men recognised its excellence, and a Dr. Stubble 
wrote a book on it entitled ti e " Indian Kectar," 
extolling its " secret virtues " as he termed its 
nutritious projierties. 
But it was not long before unscrupulous dealers, 
even at so early a date in its history, recognised 
the great facilities it rfforded for adulteration ; 
for the elder Disraeli in his " Curiosities of Litera- 
ture," tracing the cocoa to Mexico, tells us that 
"the Spaniards introduced it into Europe," but 
not in its purity, for he adds "it was a coarse 
mixture of ground cocoa and Indian corn -with 
Eacoa." 
The adulteration which began then cannot be said 
to have ceased yet, for some few years ago there 
were several prosecutions in London, and it ap- 
peared upon analysis that there was in some cases 
as much as 30 per cent, of pure starch added to 
the cocoa, and to-day can it be said tha( tberQ 
