What really happens is that, when night falls, the indifference of the caterpillars remains as great as ever. The breach in the tent provokes not a sign of excitement. They move to and fro on the surface of the nest; they work, they spin as usual. There is no change, absolutely none, in their behaviour. When the road covered chances to bring some of them to the brink of the ravine, we see no alacrity on their part, no sign of anxiety, no attempt to close up the two edges of the slit. They simply strive to accomplish the difficult crossing and to continue their stroll as though they were walking on a perfect web. And they manage it somehow or other, by fixing the thread as far as the length of their body permits. Having once crossed the gulf, they pursue their way imperturbably, without stopping any more at the breach. Others come upon the scene and, using the threads already laid as foot-bridges, pass over the rent and walk on, leaving their own thread as they go. Thus the first night’s work results in the laying over the cleft of a filmy gauze, hardly perceptible, but just sufficient for the traffic of the colony. The same thing is repeated on the nights that follow; and the crevice ends by being closed with a scanty sort of Spider’s web. And that is all. There is no improvement by the end of the winter. The window made by my scissors is still wide open, though thinly veiled; its black spindle shape shows from the top of the nest to the bottom. There is no darn in the split texture, no piece of swan’s-down let in between the two edges to restore the roof to its original state. If the accident had happened in the open air and not under glass, the foolish spinners would probably have died of cold in their cracked house. Twice renewed with the same results, this test proves that the Pine Caterpillars are not alive to the danger of their split dwelling. Expert spinners though they be, they seem as unconscious of the ruin of their work as the spools in a factory are of a broken thread. They could easily make good the damage by stopping up the breach with the silk that is lavished elsewhere without urgent need; they could weave upon it a material as thick and solid as the rest of the walls. But no, they placidly continue their habitual task; they spin as they spun yesterday and as they will spin to-morrow, strengthening the parts that are already strong, thickening what is already thick enough; and not one thinks of stopping the disastrous gap. To let a piece into that hole would mean weaving the tent all over again from the beginning; and no insect, however industrious, goes back to what it has already done.