182 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. [September 7,1872. 
retted hydrogen require a temperature of 6 - 5° and 17°, 
respectively, to produce liquids, while ethylene, with 
other faint smelling gases, is only reduced under high 
pressure at 110°. A few gases—and strangely those 
in particular that are described as having a “ foetid ” 
or “garlic” odour—present some slight exceptions 
to this singular ratio, hut it holds good so generally, 
that a list of gases arranged in order according to 
their reducible properties, and a list arranged accord¬ 
ing to their properties of smell will show a rough 
but most marked coincidence. 
ON THE CULTIVATION OE THE OLIVE, 
NEAR VENTIMIGLIA. 
BY MR. L. WINTER. 
{From a letter addressed to Mr. Daniel Manbury, F.F.S.) 
As you wish for a little information on the pro¬ 
pagation of the olive in this part of Italy, I have 
drawn up a few remarks which, though not contain¬ 
ing much that is new, may yet serve to complete 
or to confirm your own observations. 
The different lands of olive-tree we have in this 
country may be classed under three divisions :— 
1. Olivastro, the Wild Olive, Olea europcea, L., 
grows quite spontaneous, reproducing itself by seeds 
and suckers; leaves on young trees small and 
oblong,—on older trees a little larger and lanceo¬ 
late ; branches sometimes spiny ; fruit small, oblong, 
and very bitter. This kind may be regarded as the 
j>arent of all the varieties. 
2. Varieties reproducing themselves truly by 
seed, but not so freely as the olivastro, and having 
the fruit less bitter. Under this head may be placed 
the following:— 
a. Pignuole. —Branches greyish; leaves’lanceo¬ 
late, acute; fruits when ripe almost round, 
affording an oil of rather strong flavour. There 
are hundreds of these trees on the Capo Martino, 
near Mentone, quite wild. 
ft. Columbaire (Genoese dialect).—Branches 
brownish; leaves varying in shape, but mostly 
obtuse; fruit large, somewhat pointed. 
y. Spagnuole. —Fruit more elongated than the pre¬ 
ceding. These forms, a. ft. y., vary more or less 
inter se. 
3. Varieties not reproducing themselves truly by 
seed, but returning to the olivastro. That these 
varieties degenerate when propagated by seed is the 
general assertion among the people here ; but regu¬ 
lar experiments have never, I think, been carried 
on, for raising the plant by seed is not advanta¬ 
geous, suckers being of more rapid growth. In this 
division I would place two varieties, viz.:— 
a. Nilane. —Fruit large, oblong. Tins occurs in 
abundance as far west as Cannes, whence along 
the whole French coast of the Mediterranean, 
another olive with still larger fruit is cultivated. 
ft. Punginaire. —This is another variety which we 
have in this country. It has long willow-like 
leaves, and produces a very large pointed 
fruit, chiefly preferred for salting. 
The propagation of olive-trees belonging to this 
third division is effected by cleft-grafting on the 
stem of the olivastro at about six inches above the 
ground. When the scion has taken, earth is heaped 
around it, so as to stimulate it to shoot out roots. 
After three or four years the little tree begins to 
fruit, and arrived at an age of about 20 to 
25 years, the roots which have been thrown out by 
the graft send up suckers, any which come from 
those of the parent olivastro being of course extir¬ 
pated. These suckers, when about two years old, will 
be strong enough to bear separation from the parent- 
root and to be planted as independent trees. Such 
young trees fruit in three to five years after plant¬ 
ing. When a sucker is thrown out from a large 
naked root, it may be surrounded by a heap of earth 
into which it will strike roots, and in due time may 
be separated as already explained. 
The quality of the oil obtained from the cultivated 
olive very much depends on the degree of maturitjr 
of the fruit. The riper the latter, the better will be 
the oil it yields. 
Near Marseilles the olives are gathered in Octo¬ 
ber and November, while they are still unripe, and 
the oil is consequently of very inferior quality. 
This plan of anticipating the crop is adopted on 
account of the cold mistral, which spoils the olives 
sometimes completely, freezing them and rendering 
them nearly worthless for oil. To make the trees 
thicker in foliage, and thus capable of affording a 
natural shelter to their fruits, the peasants prune 
the tops every year after the gathering. In this 
district of Italy comparatively little pruning is 
needed, the trees on many properties being allowed 
to grow quite au naturel. 
About La Mortola and the adjoining district of 
Latte, as well as on all the lower slopes of the 
Riviera, the olives are frequently attacked in 
the month of July by an insect called moscliino,. 
which lays its eggs in the berry* The caterpillar 
developes itself in August, finding its nourishment 
in the pulp of the fruit. Olives thus infested drop 
from the trees while not yet fully ripe, that is, in 
October, November and December. On the moun¬ 
tains at some distance from the sea, the olives are 
scarcely at all affected by these insects ; the fruits 
in consequence attain their perfect maturity, the 
crop being gathered between December and May. 
The oil yielded by such olives is very clear and of 
superior flavour, and it commands a high price. In 
proof of this latter fact, I may remark that the value 
of the oil produced at Latte contrasted with that 
of the mountain village of San Michele at the head 
of the valley is ordinarily as three to four, some¬ 
times even as two to three. 
THE AIMS AND INSTRUMENTS OF SCIENTIFIC 
THOUGHT, f 
BY PROFESSOR CLIFFORD. 
[Continued fromp. 166.) 
I said there were two ways in which a law might 
be inexact. There is a law of gases which asserts that 
when you compress a perfect gas, the pressure of the gas 
increases exactly in the proportion in which the volume 
diminishes. Exactly; that is to say, the law is more 
accurate than the experiment, and experiments are cor¬ 
rected by means of the law. But it so happens that this 
law has been explained; we know precisely what it is 
* It appears not to lay more than one egg in each,—at 
least I have never found more than a single caterpillar in an 
olive. 
t Lecture delivered before the British Association at 
Brighton, Monday, August 19th, 1872. 
