If we look closely into the grass here on the slope of the fosse it is animated by a busy throng of insects rushing in hot haste to and fro. They must find it a labour and a toil to make progress through the green forest of grass-blade and moss and heaths and thick thyme bunches, over-topping them as cedars, but cedars all strewn in confusion, crossing and interlacing, with no path through the jungle. Watch this ant travelling patiently onward, and mark the distance traversed by the milestone of a tall bennet. First up on a dry white stalk of grass lingering from last autumn; then down on to a thistle leaf, round it, and along a bent blade leading beneath into the intricacy and darkness at the roots. Presently, after a prolonged absence, up again on a dead fibre of grass, brown and withered, torn up by the sheep but not eaten: this lies like a bridge across a yawning chasm--the mark or indentation left by the hoof of a horse scrambling up when the turf was wet and soft. Half-way across the weight of the ant overbalances it, slight as that weight is, and down it goes into the cavity: undaunted, after getting clear, the insect begins to climb up the precipitous edge and again plunges into the wood. Coming to a broader leaf, which promises an open space, it is found to be hairy, and therefore impassable except with infinite trouble; so the wayfarer endeavours to pass underneath, but has in the end to work round it. Then a breadth of moss intervenes, which is worse than the vast prickly hedges with which savage kings fence their cities to the explorer, who can get no certain footing on it, but falls through and climbs up again twenty times, and burrows a way somehow in the shady depths below. Next, a bunch of thyme crosses the path: and here for a lengthened period the ant goes utterly out of sight, lost in the interior, slowly groping round about within, and finally emerging in a glade where your walking-stick, carelessly thrown on the ground, bends back the grass and so throws open a lane to the traveller. In a straight line the distance thus painfully traversed may be ten or twelve inches; certainly in getting over it the insect has covered not less than three times as much, probably more--now up, now down, backwards and sideways, searching out a passage. As this process goes on from morn till night through the long summer's day, some faint idea may be obtained of the journeys thus performed, against difficulties and obstacles before which the task of crossing Africa from sea to sea is a trifle. How, for instance, does the ant manage to keep a tolerably correct course, steering straight despite the turns and labyrinthine involutions of the path? It is never possible to see far in front--half the time not twice its own length; often and often it is necessary to retrace the trail and strike out a fresh one--a step that would confuse most persons even in an English wood with which they were unacquainted.