35. Now this simile of Homer's is one of the best instances I can give you of the way in which great writers seize truths unconsciously which are for all time. It is only recent science which has completely shown the perfectness of this minute symbol of the power of Athena; proving that the insect's flight and breath are co-ordinated; that its wings are actually forcing-pumps, of which the stroke compels the thoracic respiration; and that it thus breathes and flies simultaneously by the action of the same muscles, so that respiration is carried on most vigorously during flight, "while the air-vessels, supplied by many pairs of lungs instead of one, traverse the organs of flight in far greater numbers than the capillary blood-vessels of our own system, and give enormous and untiring muscular power, a rapidity of action measured by thousands of strokes in the minute, and an endurance, by miles and hours of flight."* * Ormerod: "Natural History of Wasps." Homer could not have known this; neither that the buzzing of the fly was produced, as in a wind instrument, by a constant current of air through the trachea. But he had seen, and, doubtless, meant us to remember, the marvellous strength and swiftness of the insect's flight (the glance of the swallow itself is clumsy and slow compared to the darting of common house-flies at play); he probably attributed its murmur to the wings, but in this also there was a type of what we shall presently find recognized in the name of Pallas,--the vibratory power of the air to convey sound, while, as a purifying creature, the fly holds its place beside the old symbol of Athena in Egypt, the vulture; and as a venomous and tormenting creature has more than the strength of the serpent in proportion to its size, being thus entirely representative of the influence of the air both in purification and pestilence; and its courage is so notable that, strangely enough, forgetting Homer's simile, I happened to take the fly for an expression of the audacity of freedom in speaking of quite another subject.* Whether it should be called courage, or mere mechanical instinct, may be questioned, but assuredly no other animal, exposed to continual danger, is so absolutely without sign of fear. * See farther on, §148, pp. 154-156. 36. You will, perhaps, have still patience to hear two instances, not of the communication as strength, but of the personal agency of Athena as the air. When she comes down to help Diomed against Ares, she does not come to fight instead of him, but she takes his charioteer's place. "She snatched the reins, she lashed with all her force, And full on Mars impelled the foaming horse." Ares is the first to cast his spear; then--note this--Pope says: "Pallas opposed her hand, and caused to glance, Far from the car, the strong immortal lance."