It is not, however, obvious that the sudden change of direction in the translatory motion, which is commonly called a molecular shock, necessarily also affects the phase of vibration.
This change of direction corresponds to a curve in the line of volcanic fissures which have contributed their products to the building of the islands.
It works in conjunction with the disk and scroll, the cones, or the expanding pulley, to impart an intermittingly variable speed to the bobbin (each layer of the bobbin has its own particular speed which is constant for the full traverse, but each change of direction of the builder is accompanied by a quick change of speed to the bobbin).
Niven, F.R.S., called the degree table, determines the change of direction of motion of the shot while the velocity changes from V to v, to shot flying nearly horizontally, To explain the theory of this table, suppose the tangent at the point of the trajectory, where the velocity is v, to make an angle i radians with the horizon.
If a root is similarly illuminated, a similar change of direction of growth follows, but in this case the organ grows away from the light.