Now how is the work divided in this household? To discover this is no easy undertaking, for which the point of a penknife will suffice. He who proposes to inspect the burrowing insect in its home must resort to exhausting excavations. We have not here the chamber of the Sacred Beetle, the Copris or other Beetles, which is uncovered without trouble with a mere pocket-trowel; we have a shaft whose floor can be reached only with a stout spade, manfully wielded for hours at a stretch. And, if the sun be at all hot, you return from your drudgery, feeling utterly worn out.
Oh, my poor joints, grown rusty with age! [[86]]To suspect the existence of a beautiful problem underground and to be unable to dig! The zeal survives, as ardent as in the days when I used to demolish the spongy slopes beloved of the Anthophoræ;[3] the love of research has not abated; but my strength fails me. Fortunately I have an assistant in the person of my son Paul, who lends me the vigour of his wrists and the suppleness of his back. I am the head, he is the arm.
The rest of the family, including the mother—and she not the least eager—usually go with us. You cannot employ too many eyes when the pit becomes deep and you have to observe from a distance the tiny objects unearthed by the spade. What one overlooks another will detect. Huber,[4] when he was blind, studied the Bees through the intermediary of a clear-sighted and devoted helper. I am even better off than the great Swiss naturalist. My sight, which is still fairly good though much worn, is assisted [[87]]by the perspicacious eyes of all my family. I owe it to them that I am able to continue my research-work: let me thank them here and now.
We are on the spot early in the morning. We find a burrow with a large mound formed of cylindrical plugs forced out as though by blows of the hammer. We clear away this hillock and a pit opens below it. A good, long reed, gathered on the way, is inserted in the hole. Pushed farther home, as the surface soil is cleared away, it will serve us as a guide.
The soil is quite loose, unmixed with pebbles, which are obnoxious to the digging insect that loves the perpendicular and especially obnoxious to the cutting edge of the exploring spade. It consists solely of sand cemented with a little clay. The digging would therefore be easy, if one had not to reach depths in which tools become extremely difficult to handle unless the whole area is overturned. The following method gives good results without unduly increasing the volume of earth removed, a procedure to which the owner might object.
A space of roughly a yard in radius is attacked around the shaft. As the guiding [[88]]reed is laid bare, we push it lower in. It began by going about nine inches underground, it is now eighteen inches down. Soon it becomes impracticable to remove the earth with the spade, which is hampered by lack of room. We have to go on our knees, collect the rubbish in both hands and toss it outside. The more we do so, the deeper the hole becomes, increasing the already enormous difficulty. A moment arrives when, to continue, we are obliged to lie flat on our stomachs and dip the front of our bodies into the hole, as far as our more or less supple waists allow. Each dip flings up a good handful of earth. And the reed goes lower and lower, without giving any indication of an immediate check.
It is impossible for my son to continue in this fashion, despite his youthful elasticity. To reach the bottom of the disheartening cavity, he lowers the level of the sustaining soil. A cut is made at one side of the circular pit, giving just enough space to admit his two knees. This is a shelf, a ledge, which will be lowered as we go on. The work is resumed, this time more actively; but the reed, when we consult it, descends, descends to a great depth. [[89]]
We lower the supporting shelf still more and employ the spade again. When the rubbish is removed, the excavation is more than three feet deep. Are we there at last? Not at all: the terrible reed dives still lower down. Let us sink the ledge again and continue. Perseverance is rewarded. At four feet and a half, the reed touches the obstacle; it goes no farther. Victory! The task is done: we have reached the Minotaur’s chamber.
The pocket-trowel discreetly lays it bare and the occupants appear: first the male, and, a little lower down, the female. When the couple are removed, a dark, circular patch is seen: this is the top of the column of provisions. Let us be careful: dig gently! What we have to do is to cut away the central clod at the bottom of the pit, to separate it from the surrounding earth and then, slipping the trowel underneath and using it as a lever, to extract the block all in a lump. There! That’s done! We have the couple and their nest. A morning of arduous digging has procured us these treasures: Paul’s broiling back can tell us at the cost of what efforts.
This depth of nearly five feet is not and [[90]]could not be uniform: there are many causes that induce it to vary, such as the degree of moisture and consistency in the soil traversed, the insect’s passion for work and the time available, according to the more or less remote date of the egg-laying. I have seen burrows dip a little deeper; I have seen others reach not quite three feet. In any case, Minotaurus, to settle his family, requires a lodging of extravagant depth, such as is dug by no other burrower of my acquaintance. Presently we shall have to ask ourselves what imperious needs oblige the collector of Sheep-droppings to dwell at such depths.