In our vocabulary "feminine" means feeble; but in the Insect World it is the synonym of strength and energy. It is,--as is the case with maternity everywhere,--it is for the purpose of defending and nourishing the child, of provisioning the cradle in which the orphan will remain alone,--it is for this purpose specially that the insect is a warrior, and furnished with formidable weapons. As far as concerns the instruments which pierce, and cut, and saw, the insect, in spite of all our progress, is perhaps a little in advance of man to-day. The instinct of maternity, the need of providing for its child--the future orphan--the protecting shelter of the hardest bodies, has evidently inspired it to make extraordinary efforts for the development and refinement of its tools. A few, in their fantastical character, have as yet no analogues in any of our factories. Long before Réaumur organized the thermometer, the ants, for the protection of their delicate, hygrometrical, and susceptible eggs, divided their habitations into a series of thirty or forty stories,--lowering or raising the tiny creatures to the degree of warmth, dryness, or humidity, which the temperature of the day and of the hour of the day rendered necessary. Thus they formed an infallible thermometer, on which one might rely with as much certainty as on that of the philosophers. In the comparisons between human and insect industry, the differences which we remark belong not so much to the methods as to the speciality of their wants and situation. The insect aptly varies the application of its arts. For example: the spider which, in its network-trap, improvised every day, lightens its work by a mixture of gluing and spinning, follows quite a different process in the important labour of fabricating the soft, warm, and durable cocoons which are intended to receive its young. The nest would seem to be partly spun and partly felted, like the majority of birds' nests. We know that from the water-spider man derived the idea of the diving-bell; but it is _not_ generally known that an ingenious Norman peasant has succeeded in imitating perfectly the operations of the larva of the syrphes, which, by means of an extremely prolonged respiratory apparatus, preserves a communication with the pure and wholesome air, even while working at the bottom of the most putrid waters.