(fig. 2); had we not this information on the best authority
(Vuillaume and Fetis), it might be imagined that some of the bows
figured by Mersenne,[17] e.g. the bass viol bow KL (p. 184), and another
KLM (p. 192), had a movable nut and screw; the nut is clearly drawn
astride the stick as in the modern bow. Mersenne explains (p. 178) the
construction of the bow, which consists of three parts: the _bois,
baton_ or _brin_, the _soye_, and the _demi-roue_ or _hausse_. The term
"half-wheel" clearly indicates that the base of the nut was cut round so
as to fit round the stick. In the absence of any allusion to such
ingenious mechanism as that of screw and nut, we must infer that the
drawing is misleading and that the very decided button was only meant
for an ornamental finish to the stick. We are informed further that _la
soye_ was in reality hairs from the horse or some other animal, of which
from 80 to 100 were used for each bow. The up-stroke of the bow was used
on the weak beats, 2, 4, 6, 8, and the down-stroke on the strong beats,
1, 3, 5, 7 (p. 185). The same practice prevailed in England in 1667,
when Christopher Simpson wrote the _Division Viol_. He gives information
concerning the construction of the bow in these words: "the viol-bow for
division should be stiff but not heavy. The length (betwixt the two
places where the hairs are fastened at each end) about seven-and-twenty
inches. The nut should be short, the height of it about a finger's
breadth or a little more" (p. 2).

As soon as Corelli (1653-1713) formulated the principles of the
technique of the violin, marked modifications in the construction of the
bow became noticeable. Tartini, who began during the second decade of
the 18th century to gauge the capabilities of the bow, introduced
further improvements, such as a lighter wood for the stick, a straight
contour, and a shorter head, in order to give better equilibrium. The
Tourtes, father and son, accomplished the rest.

After Francois Tourte, the following makers are the most esteemed:
J.B. Vuillaume, who was directly inspired by Tourte and rendered an
inestimable service to violinists by working out on a scientific basis
the empirical taper of the Tourte stick, which was found in all his
bows to conform to strict ratio;[18] Dominique Peccate, apprenticed to
J.B. Vuillaume; Henry, 1812-1870, who signs his name and "Paris" on
the stick near the nut; Jacques Lefleur, 1760-1832; Francois Lupot,