138 
ANIMAL INTELLIGENCE. 
lie found his provisions in the safe swarming with ants as 
before, and on investigating their mode of access to them 
found — 
Proceeding along the whitewashed wall a string of ants 
going and coming from the outer door to a height of four feet 
on my wall, and corresponding with that of the safe ; and look- 
ing between it and the wall, I discovered the secret — the bridge 
which these persevering little insects had made. 1 1 consisted of 
a broken bit of straw, which rested with one end on a mud 
buttress fixed to the wall, and the other on the overhanging oi 
projecting top of the safe, which came within an inch and a half 
of the wall. So they must have carried the straw up from the 
floor, and resting their end of it on the support they had pre- 
pared, let it fall until its other end reached the safe, and then 
crossed and completed the structure, for it was fastened at both 
ends with the mortar composed of their saliva and fine earth. 
Buthlessly I destroyed the bridge, and moving the safe farther 
from the wall, managed to prevent their inroads for that season 
at least. Since then I have frequently seen short bridges, com- 
posed entirely of the concrete or mortar which the white ants 
use to cover up their workings, extending from a damp earthen 
wall to anything not more than three-quarters of an inch 
from it. 
Of the Ecitons Mr. Belt says : — 
I shall relate two more instances of the use of a reasoning 
faculty in these ants. I once saw a wide column trying to pass 
along a crumbling, nearly perpendicular slope. They would 
have got very slowly over it, and many of them would have 
fallen, but a number having secured their hold, and reaching 
to each other, remained stationary, and over them the main 
column passed. Another time they were crossing a watercourse 
along a small branch, not thicker than a goose-quill. They 
widened this natural bridge to three times its width by a 
number of ants clinging to it and to each other on each side, 
over which the column passed three or four deep; whereas 
excepting for this expedient they would have had to pass over 
in single file, and treble the time would have been consumed. 
Can it be contended that such insects are not able to determine 
by reasoning powers which is the best way of doing a thing ? 
Another observer, writing from the same part of the 
world to Buchner, gives a still more wonderful account of 
the ingenuity of Ecitons in crossing water. This observer 
