"In the technical field, the phase of violin technic which is less
developed, it seems to me is, in most cases, bowing. One often notes a
highly developed left hand technic coupled with a monotonous and
oftentimes faulty bowing. The _color_ and _variety_ of a violinist's art
must come largely from his intimate acquaintance with all that can be
accomplished by the bow arm. The break or change from a down-bow to an
up-bow, or _vice versa_, should be under such control as to make it
perceptible only when it may be desirable to use it for color or
accentuation.