The breath directed horizontally across the open end, impinged against the sharp inner edge of the pipes, creating the regular series of pulses which generate the sound waves within the tubes.
As the supply of sodium was increased, the lines, besides becoming broader, did so unsymmetrically, and a shaded wing or band appeared on one side or the other according as the beam impinged on one side or the other of the flame.
originally impinged on that at rest is now represented by the energy, kinetic and potential, of the small motions of the individual molecules.
The sustaining of the whole, therefore, depended upon the speed at which it travelled through the air, and the angle at which its under surface impinged on the air in its front....
aluminous porphyroblast impinged on a quartz-rich pseudomorph, it did not replace the quartz.