A further evidence of their sense of smell is the anger they manifest on the crushing of one of their number. Like the terror inspired into an ox by the smell of freshly-drawn blood in the slaughter-house, is the odour of a bruised comrade to bees. Again, the smell of the liquid from one of their poison bags excites them strongly. A wound just made by a sting rouses others to inflict more wounds; and, if the fluid be presented to them at the entrance of their homes, it at once stirs their fury. If, however, it be allowed to crystallise, and thus to become incapable of emitting any odour, it will be quite disregarded by the bees. Sir John Lubbock tried various experiments with eau-de-Cologne and rose-water, and found that, till the insects had become habituated by frequent use to these liquids, they always came out to the entrance, to ascertain the meaning of the odours which had penetrated into the hives. It is well known, also, that they dislike the smell of paint so much, that it is not advisable to place a swarm in a freshly painted box, lest they should forsake it, from its unpleasant odour. We may well conclude that it is owing to the keenness of this sense that they perceive the presence of flowers containing nectar; and, guided by it, they wing their flight to distant fields where the white clover attracts them, or to more barren districts where the heath promises them abundant pasturage. It is very certain that the fragrant aroma of honey is at once perceived by them at many feet from their dwellings; and in taking their sweets from them it is, for this reason, necessary to avoid all exposure of broken combs, or the dripping of their contents. Great trouble is, in fact, often occasioned by the readiness with which they thus detect the presence of their own produce. Within our personal knowledge, at a provincial show of bees, hives, and honey, the fragrance of the liquid attracted bees from the neighbourhood in such immense numbers that they carried off, during one afternoon, some seventy pounds of honey from the tent in which it was being exhibited.