EXPERIMENTS OF M. LLAMBIAS. 
457 
the extremity of which was placed a common 
lamp ; a copper wire conducted the electricity 
from the flame to an electroscope. On rainy 
or windy days, a very thin portion of phos- 
phorus was substituted for the lamp, and was 
kept in a tube of glass terminating in a point. 
He found, that whenever the electricity of the 
atmosphere is positive (which is always the 
case in calm weather), it is impossible to 
have any traces of electricity in the interior 
of a wood. The most curious mode of observ- 
ing it, is to move, carrying the electroscope 
in the hand, either out of the wood, or above 
the leaves. The flame is scarcely removed 10 
paces from the trees, when traces of electri- 
city begin to appear. These increase with 
the distance. In returning, the first tree is 
scarcely reached, when the electroscope 
ceases immediately to indicate the presence of 
electricity. These general results can only be 
explained by one of two hypotheses ; either, 
that the electricity of the air is discharged by 
the leaves and the vapour of water, and 
escapes by this means into the earth, or, that 
there is developed by the effect of vegetable 
life, — by the respiration of plants, enough of 
negative to neutralize the positive electricity 
of the surrounding air. The second hypo- 
thesis appears most plausible, because it is 
difficult to admit the second, when we attend 
to the conducting power of the flame, and of 
the column of hot air which is much superior 
to that of the leaves. 
The results of a great number of observa- 
tions showed that in the night, signs of elec- 
tricity are often absent, both in the air, and 
in the interior of a wood. At the approach of 
day, before the sun appears above the hori- 
zon, decided indications of negative electricity 
appear among the trees, while none are detect 
ed in the open air. We can readily under- 
stand this observation, if we admit that 
oxygen is disengaged from the leaves before 
the rays of the sun strike them directly. In 
this case, negative electricity appears. If the 
sky is calm, the signs of negative electricity 
disappear in the interior of the wood, at the 
same time that positive electricity is developed 
in the air- On three days, when the sky was 
cloudy, and almost stormy, negative electri- 
city was detected in the external air, and in the 
wood. Hence, it may be inferred, that ne- 
gative electricity is disengaged by vegetation 
during the dry, which is constantly neutra- 
lized by positive electricity. Matteuci has 
promised to continue his observations, 
and expresses a strong desire that similar 
investigations should be undertaken by 
meteorologists in other parts of the world, 
especially in reference to rain.* 
NEW METHOD OF MAGNETIZ- 
ING. — M. Aime recommends the following 
method, which consists in tempering and 
magnetizing a bar of iron at the same time. 
To effect this, a bar of soft iron curved in the 
form of a horse-shoe, is surrounded with a 
brass wire, covered with silk ; the two ex- 
* BibUotbeqne Universelle, May, 1835, 33, 
tremities of this wire are made to communi- 
cate with the poles of the voltaic pile ; a bar 
of steel equal in length to the distance 
betw’een the two extremities of thehorse-shoe 
is then ignited, and seized between a pair 
of pincers; the two poles of the horse -shoe 
are then applied to the bar, and plunged into 
a bucket of water ; in the course of a minute 
or two after immersion, the bar is detached 
from the horse-shoe, and a|similar operation 
performed with similar bars extracted from 
the fire. In order to prevent the brass wire 
from softening, care must be taken in dip- 
ping the apparatus in water to envelope the 
two extremities of the helix in a rag covered 
with mastic. The ends of the conducting 
wire were soldered to the zinc and copper 
poles of the battery ; a single wire was em- 
ployed. Aime, however, considers that it 
may be preferable to unite several into a 
bundle, or even to take a ribbon of copper 
covered with silk or varnish. The bar ought 
not to be detached too quickly from the 
horse-shoe ; it is necessary to wait until the 
interior of the steel has acquired a slight 
elevation of temperature, in order that the 
molecules may have time to arrange jthem- 
selves, conveniently, for magnetizing and 
tempering. The duration of the immersion 
varies with the size of the bar, and the 
temperature which it possesses when taken 
from the fire.* 
9 MAGNETISM BY COMMON ELEC- 
TllICITY.f — M. Llambias has addressed a 
manuscript upon this subject to the French 
academy. The results of his experiments 
were, 1. In every metallic conductor travers- 
ed by the discharge of a Leyden phial, two 
magneto- electric currents are simultaneously 
discharged, which pass in opposite directions, 
one of which may be said to proceed from the 
vitreous to the resinous pole, and the other 
from the resinous to the vitreous pole. 2. The 
currents can be partly separated from each 
other. This separation may be effected in 
dividing a discharge between two or several 
different branches of the same circle, when in 
some particular branch there is an interrup- 
tion which gives origin to the spark. 3. This 
separation of currents is more or less practi- 
cable, and is comprised within certain limits, 
which can be nearly determined by experi- 
ments for each discharge, and for each of the 
other elements which produce the phenome- 
non. 4. The separation of these currents may 
take place in any portion of the circle sub- 
mitted to the discharge, at the same time 
that the other parts of the same circle are 
traversed by currents completely re united. 5. 
In every circle, or every portion of the circle, 
which the two currents traverse in union, it 
is, in general, the current which passes from 
the vitreous to the resinous pole, or the pri- 
mitive current which has the chief effect in 
communicating the magnetic influence. 6. 
Each of the currents magnetizes so much the 
* Journal de Chime. Medic, i. 370. 
t Ibid, i 3S, 
