So agreeable is the action of the machine, that when the motion is altogether stopped the child will often cry, or rather coo, that the movement may be repeated.
By turning a small handle the machine is very gently set in motion, but by pressing down a knob its velocity may be increased at will.  So agreeable is the action of the machine, that when the motion is altogether stopped the child will often cry, or rather coo, that the movement may be repeated.  For the second stage, the instrument is similar to the first, but larger and stronger.