speculum

‘spekcu-lom x. [ploral specula, speculums] an ocellus or eyezspet, as of a peaceck’s tail; also, the mirror of a wing, a specially colord, eften iridescent area en some of the flight-fethers; the mirror. speed sprid n. rapidity of movement; swiftne ; veleczty. air speed, the speed of a fly bigiabtlehene telattv to the air thru which it 1s pa tng: distinguisht from land. speed. land speed, the speed of a flying-machine relatav to the land-surface or earth beneath: distinguisht from air speed. law of corresponding speeds, the law that when the speed of a gtven aircraft or medel 1s to that of another simular craft as the square roots of their lrmear mesurements, their resistances are as to their respectiv ma es, or as the cubes. of their lrmear mesurements.