In January 1859 issue of Journal of the Franklin
Institute published a Notice of Mr. L. C. Stephens’
Patent Combination Rule.
The notice contains a detailed description of the tool
and various examples of the use of this Combination
The Stephens & Co. produced this rule based on
the patent No. 19,105 granted to Lorenzo C. Stephens
on January 12, 1858.
The rule is made of boxwood or
ivory and combines in itself a carpenter's rule,
spirit-level, square, plumb, bevel, indicator,
brace-scale, draughting scale, T square, protractor,
right-angled triangle, and with a straight edge can
be used as a parallel ruler.
I included a few photographs showing the
Combination Rule most likely made in the 1860s,
before an introduction of a model numbering system.
Instead of the well-known designation of this rule
as a No. 36, stamped on the body of the rule; mark
shows only a patent date. WK
To the Committee on Publications: Notice of Mr. L.
C. Stephens’ Patent Combination Rule
Gentlemen: As all simple and comparatively accurate
instruments for the use of engineers and mechanics,
whereby they are enabled with facility to make
measurements and calculations are of importance, I
would call their attention through your Journal to a
combination rule manufactured by L. C. Stephens &
Co., of Pine Meadow, Connecticut.
This rule is composed of two arms of 6 inches in
length, each folding together by one joint; when
folded, it is 1-3/8 inches wide and 3/8 of an inch
thick, and is protected by strong brass binding; its
weight only slightly exceeds the ordinary pocket
The combination consists of its having a spirit
level let into the upper brass binding of one of the
six-inch arms - the glass is let into the rule and
protected by a brass plate put on with screws, and
therefore can be removed and replaced in case it
should accidentally be broken.
There is a steel blade shutting into the other arm,
having the axis upon which it moves near the
opposite extremity from the joint of the two arms
When this blade is opened out from the arm, and is
raised so as to form an angle of 90° with said arm,
it is prevented from opening further by two stops in
the arm, one placed below the axis and the other
The upper arm, or that containing the level, can
then be closed down - the steel blade fitting into a
slit at the outer end of the arm. In this end there
is an eccentric, which, at pleasure, can be made to
press slightly against the blade, and thus hold it
One side of the blade is marked with lines which
show the value of the angle formed by the two arms
of the rule, the blade being moved until the under
edge of the slit arm is coincident with the mark on
the blade showing the required angle then the two
inner, or two outer edges of the arms will show the
containing lines of the angle.
The other side of the blade is marked in inches and
twelfths. The inner edge of the arm in which the
blade closes is also divided into inches and
twelfths, so that when the blade is in a position at
right angles with this arm it may form a brace
The inner edges of the arm holding the level is also
marked, so that it may show the angle formed by the
blade and its own arm.
The arms on their sides are divided into inches,
eighths, and sixteenths, as in ordinary rules, also
into tenths of inches, and also into several scales
for the convenience of draughtsman.
The uses of this convenient little instrument are
very numerous. When the blade is
closed into its arm and the arms are shut together,
it is a spirit level.
When the blade is opened at an angle of 90° with its
arm, and the other arm shut down so that the slit
holds the blade rigid, the blade is perpendicular to
the edge containing the level, and the instrument
can then be used as a plumb.
The combination of a level and moving blade, and arm
for obtaining angles, will, to any one in possession
of the instrument, suggest various methods of
obtaining heights, distances, &c.
Besides the above uses, for all measurements
requiring only the ordinary foot rule, it will, from
the sub-divisions on the sides of the arms, answer
H. J. T.
1. Image with a patent
background courtesy of
Jim Bode Tools.com
2. Images courtesy of