and again made for the stake. This manoeuvre was repeated several
times, but finally, as if discouraged, the vine abandoned the pursuit
and ignoring further attempts to divert it traveled to a small tree,
further away, which it climbed.

"Roots of the eucalyptus will prolong themselves incredibly in search
of moisture. A well-known horticulturist relates that one entered an
old drain pipe and followed it until it came to a break, where a
section of the pipe had been removed to make way for a stone wall
that had been built across its course. The root left the drain and
followed the wall until it found an opening where a stone had fallen
out. It crept through and following the other side of the wall back
to the drain, entered the unexplored part and resumed its journey."

"And all this?"

"Can you miss the significance of it? It shows the consciousness of
plants. It proves that they think."

"Even if it did--what then? We were speaking, not of plants, but of
machines. They may be composed partly of wood--wood that has no
longer vitality--or wholly of metal. Is thought an attribute also of
the mineral kingdom?"

"How else do you explain the phenomena, for example, of
crystallization?"

"I do not explain them."

"Because you cannot without affirming what you wish to deny, namely,