AND HORTICULTURE. 3 
to the earth or vice versa. The existence of these currents 
has been proved beyond all doubt through the experiments 
of the Finnish International Polar Expedition of 1882-84. 
§ 2. My reasons will be shown in the following order :— 
(2) The physiology of plants gives a satisfactory expla- 
nation of the functions which most of their organs have to 
perform, and good reasons for their existence and their 
varying forms. This is, however, not the case with the 
needle-like shape of the leaves in fir trees, and the beard 
on the ears of most cereals. Since nothing exists without 
a purpose in all the infinite number of objects in Nature, 
then the needle-shaped leaves and the beard must have 
their determined ends. In fact, they are very well fitted to 
be the means through which the electricity goes from the 
atmosphere into the earth, or vice versa; thatis to say, they 
act in the same fashion as metallic points. To pretend that 
they really serve as a means of transmitting electricity only 
because their form shows them capable of it would be to 
go too far. The presence of electricity in the air around 
them shows that they are, in fact, in a position to perform 
this function of transmission. Through experiments made 
during the above-named expedition, it was, at least by 
analogy, proved that they really serve that end, for it was 
not only shown that such electrical currents exist, but these 
currents were even measured by means of a specially con- 
structed apparatus provided with metallic points. 
We are thus induced to concede that an electrical current 
is going on through the needle-formed leaves of the pine, 
and the beard on the ears of cereals, not to particularise 
other plants. Though this is the case, it is not, however, 
shown that this electrical current exercises any influence 
whatever in the process of vegetation, or, in other words, 
has any definite effect on the plant life itself. That must 
be proved by experiments, and a description of them, with 
an exposition of their results, is the principal object of this 
volume. 
B2 
