In one of our forums, there was a question of when & who had the 1st open handle adjustable wrench.
today I was looking up a wrench in Don Shockley's "Wrenches & Patents book and remembered the
request, so I then got sidetracked on that subject.
in his listing with pictures showing open handle wrenches, the 1st of each were listed as;
monkey wrench; patent 56628 July 24, 1866 to R. S. Stetson
adjustable wrench; patent 89517 April 27, 1869 to G. C. Taft
George C. Taft, Worcester, Massachusetts
spent more time looking into this subject, going thru Cope's 1830-1930 wrench book, and double checking with DATAMP, it seems that the open adjustable may have come out earlier,
Hood & Perkins, Worcester, Mass. listed one in 1866 using the rack and rotary screw arrangement
to adjust the jaws. patent # 17,531
info from DATAMP shows the wrench with "GREEN RIVER WORKS" on it, DATAMP states that
Mr. Hood was Superintendant at Green River Works in 1857
* as of now, the adjustable's earliest open handle date is 1866/1867 until we find an earlier one.