That vertical currents or components of air-motion having a velocity of several meters per second occasionally occur in the lowest tow kilometers of the atmosphere is an observed fact, but we are far as yet from compleate knowledge as to the conditions which produces such motion

I suggest, however, that wave-motion proper, that is low-velocity, periodic oscillations of pressure or temperaturem whether transmitted from a distant source of disturbance, or occurring under the continuous interaction of two horizontal currents of air can be ruled from any list of hypothetical causes of important vertical motion.