The patent is almost as interesting as the wrench.
The patent shows slightly curved handles, and clearly describes the advantage of the curvature:
The handles 1, 1 are precisely identical and termi-
nate in the substantially identical curved
portions...
Because the handles are curved and paral-
lel to each other in the position indicated,
they are readily manipulated by the fingers
and when grasped by the hand of the oper-
ator present a smooth even surface in the
palm of the hand, making a wrench which so
can be used indefinitely without tiring the
hand.
And all the claims describe the object of invention as "
A wrench comprising opposed pivotal members, with parallel handle bars which
are identical in form and curved to one side ...
Which means if poor Wade had ever had to defend his patent from infringment, he probably would have lost if the wrenches all looked like the one above ;P
