Let us try to devise something better. In a dimly-lit corner of my study I hang perpendicularly a glass tube of smaller calibre than the first. I leave it as it is, unprovided with an opaque sheath. At the bottom is a nine-inch column of earth. All the rest is empty and may be easily observed, if the Minotaurs consent to work under such disadvantageous conditions. Provided that the experiment be not unduly prolonged, they do consent and very readily, so imperious is the need of a burrow as laying-time draws nigh. I extract from the soil a couple engaged in excavating their natural shaft and place them in the glass tube. Next morning I find them continuing their interrupted business in broad daylight. Seated a little way off, in the shadow of the corner in which the apparatus hangs, I watch the operation, amazed by what I see. The mother digs. The father, at some distance, waits until the heap of rubbish is beginning to hamper the worker’s movements. Then he approaches. By small armfuls he draws towards him and slips beneath his abdomen the shifted earth, which, being plastic, forms into a ball under the pressure of the hind-legs. The Beetle now turns about beneath the load. With the trident driven into the bundle, as a pitchfork is driven into a truss of hay, before tossing it into the loft, the fore-legs, with their wide, toothed shanks, gripping the load and preventing it from crumbling, he pushes with all his might. And cheerily! The thing moves and ascends, very slowly, it is true, but still it ascends! How is it done, seeing that the too smooth surface of the glass acts as an absolute check to the upward movement? The insurmountable difficulty has been provided for. I selected a clay soil likely to leave a trace of its passage. With the cart before the horse, the load itself sands the road and makes it practicable; in rubbing past every portion of the wall, it leaves particles of earth which constitute so many points of purchase. Therefore, as he pushes his burden upwards, the Beetle finds behind it a roughened surface which affords him a footing as he climbs. This, after all, is all he needs, though it involves occasional slips and efforts to retain his balance, which are unknown in the natural shaft. When he comes to a certain distance from the opening, he leaves his clod, which, shaped by the tube, remains in its place, motionless. He returns to the bottom, not by allowing himself to fall suddenly, but gradually and carefully, by means of the footholds by which he made his way up. A second pellet is hoisted up and welded to the first. A third follows. At length, with a last effort, he pushes out the whole thing in a single plug.