redominantly Pennsylvania-German settlement, the
plane used by Miller conforms to the Sheffield type illustrated in the
catalogue of the Castle Hill Works as shown in figure 33. (York County
Historical Society, York, Pa.)]

[Illustration: Figure 35.--1820: JOHN BRADFORD'S shop sign carved by
Isaac Fowle is a unique documentary of early 19th-century tool shapes
and is in the Bostonian Society, Boston, Mass. (Index of American
Design, The National Gallery, Washington, D.C.)]

[Illustration: Figure 36.--1703: THE JOINER'S brace and bit--a detail
from Moxon, _Mechanick Exercises_ ..., London, 1703. (Library of
Congress, Smithsonian photo 56635.)]

[Illustration: Figure 37.--1769: ROUBO'S ILLUSTRATION OF THE BRACE and
bit differs from Moxon's only in the precision of the delineation.
Contrast this form with that of the standard Sheffield version in figure
38 and the metallic braces illustrated in figures 40 through 44. From
these plates can be seen the progression of the bitstock toward its
ultimate perfection in the late 19th century. (Andre-Jacob Roubo, _L'Art
du menuisier_, 1769.)]

[Illustration: Figure 38.--EARLY 19TH CENTURY: THE MASS-PRODUCED VERSION
of the wooden brace and bit took the form illustrated in Book 87 of
Cutler's Castle Hill Works. (_Courtesy of the Victoria and Albert
Museum._)]

[Illustration: Figure 39.--18TH CENTURY: THE TRANSITIONAL FORM of the
wooden brace and bit incorporated the overall shape of the mass-produced
version but retained the archaic method of fastening the bit to the
chuck. The tool is of Dutch origin and suggests the influence of
Sheffield design on European tools. (Smithsonian photo 49792-E.)]

[Illustration: Figure 40.--1769: ROUBO ILLUSTRATED THE METALLIC BRACE
and, in addition, suggested its use as a screwdriver. (Andre-Jacob
Roubo, _L'Art du menuisier_,1769.)]

[Illustration: Figure 41.--ABOUT 1775: FORD, WHITMORE AND BRUNTON made
and sold clockmaker's braces of metal with a sweep and shank that was
imitated by American patentees in the 19th century. (Catalogue of Ford,
Whitmore and Brunton, Birmingham, England. _Courtesy of the Birmingham
Reference Library._)]

[Illustration: Figure 42.--1852: NEARLY ONE HUNDRED YEARS after Roubo's
plate appeared, Jacob Switzer applied for a patent for an "Improved Self
Holding Screw Driver." The similarity of Switzer's drawing and Roubo's
plate is striking. (Original patent drawing 9,457, U.S. Patent Office,
Record Group 241, the Nat