78' 
VARIETIES. 
these disorders, ozone was very abundant in the air. On the other hand, it 
has been said that its deficiency in air will account for cholera or fevers, 
since the foul effluvia or miasmata giving rise to these diseases are not com- 
pletely destroyed or removed by the oxidizing action of ozone. These of 
course, are mere speculations insusceptible of proof ; but in the meantime, 
it, must be conceded that the subject opens a new road to experiment and 
observation,, and that very important results may be obtained by following 
out Sehonbein's researches. — London Medical Gazette, June 20th, 1851. 
On the Siphonia, or India-Rubber Tree. By Richard Spruce, Esq. — 
The Seringue-tree has long been known to exist abundantly on the Rio 
Madeira, but it is only during the present year that it has been found to 
grow on the Ramos in considerable quantity. 
After breakfast the Capitao accompanied us into the forest, and showed 
us the Seringue-trees, and the mode of collecting the milk. A track had 
been cut to each tree, as also to adjacent flats of Urucuri palm (Cocos coro- 
nata, Mart.) which, curiously enough, is almost invariably found along with 
the Seringue, and whose fruit is considered essential to the proper prepara- 
tion of India-rubber. A stout sipo is wound round the trunk of the Seringue, 
beginning at the base and extending upwards about as high as a man can 
reach, and making in this space two or three turns. This sipo supports a 
narrow channel made of clay, down which the milk flows as it issues from 
the wounded trunk, and is received into a small cuya deposited at the base. 
Early in the morning a man goes into the forest and visits in succession 
every tree, taking with him a terc/ado and a large cuya (called cuyamboca) 
suspended by a handle so as to form a sort of pail. With his tergado he 
makes sundry slight gashes in the bark of each tree, and returning to the 
same in about the space of an hour he finds a quantity of milk in the cuya 
at the base, which he transfers to his cuyamboca. The milk being collected 
and placed in a large shallow earthern-ware pan, several large caraipe-pots, 
with narrow mouths, are nearly filled with the fruit of the Urucuri and 
placed on brisk fires. The smoke arising from the heated Urucuri is very 
dense, and as each successive coat is applied to the mould (which is done 
by pouring the milk over it, and not by dipping it into the milk,) the 
operator holds it in the smoke, which hardens the milk in a few moments. 
The moulds now used are all of wood, and not of clay as formerly, and the 
one generally preferred is in the form of the battledores which English 
housewives use for folding linen, only thinner, and flat on both sides, and 
the milk is applied only as far as to the insertion of the handle, the latter 
being held by the operator. When the requisite number of coatings has 
been applied, and time has been allowed for the whole to stiffen, the seringue 
is withdrawn from the mould by slitting it along one side and end. In this 
state it is known in the Para market as Seringue em couro, or hides of India- 
rubber, and it is preferred to the bottle-rubber by purchasers. I send you 
