An Improvement in Rules, T Squares, Levels, and Set Squares, to Enable them to be Accurately Set for Indicating Angles.
Year: 1888

page_text: Date of Application, 8th Aug., 1888
Complete Specification Left, 18th May, 1889-Accepted, 27th July, 1889
PROVISIONAL SPECIFICATION.
An Improvement in Rules, T Squares, Levels, and Set Squares, to
Enable them to be Accurately Set for Indicating Angles.
JOSEPH PARKINSON, Electrician South Regent Street Lancaster CHARLES
FREDERICK PARKINSON Engineer South Regent Street Lancaster SAMUEL FAWCETT
Photo Engraver Portland Street Lancaster do hereby declare the nature of this
invention to be as follows:-
Our invention consists of a slide or slot, a carriage and radial arm or arms.
When our invention is applied to jointed rules, we fix to one leg of the rule, tho
slide or slot; which can be made of metal and fixed to, or can be cut in the leg of
the rule.
In this slide or slot, the carriage (which may be made of metal or any hard material)
slides.
On the other leg of the rule, we hinge by its one end or ends, the radial arm or
arms; while the other end or ends engage in the said carriage.
To use our improvement, tho legs of the rule are pulled apart until a line
on the carriage coincides with the line on the slide or slot, indicating the angle
required.
When our invention is applied to Ṭ squares the radial arm or arms may be
attached by its hinge to the head of the † square; (which head must be hinged
to the blade in the usual and well known way) while the slide or slot, with
its carriage, may be fixed to or cut in the blade of the T square.
When our invention is for improvements in set squares, we have two legs similar
to a two feet rulo; the radial arm or arms being as before hinged at one end or ends
and the other end or ends engage in the carriage. The slide or slot may be either
attached to, or made part of the instrument.
When our invention is applied to levels, the leg which carries the slide or slot is
hinged to the under side of the level, while the radial arm or arms are hinged to the
level itself. Or, the radial arm or arms may be hinged to the leg, while the slide or
slot carrying the carriage may be fixed to, or cut in the level.
Dated this Seventh day of August 1888
JOSEPH FARKINSON.
CHARLES FREDERICK PARKINSON.
SAMUEL FAWCETT.
COMPLETE SPECIFICATION.
An Improvement in Rules, T Squares, Levels, and Set Squares, to
Enable them to be Accurately Set for Indicating Angles.
JOSEPH PARKINSON Electrician South Regent Street Lancaster SAMUEL FAWCETT
Photo-engraver Portland Street Lancaster CHARLES FREDERICK PARKINSON Engineer
South Regent Street Lancaster do hereby declare the nature of this invention and
in what manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :—
Our invention relates to means or apparatus to enable rules, T squares, levels and
set squares, to be accurately set for indicating angles. Reference to drawings is
necessary. It consists of a slide or slot (A) a carriage (B) and a radial arm or
arms (C).
When our invention is applied to jointed rules, we fix to one leg of the rule, the
slide or slot (A), which may be made of metal and fixed to, or cut in the leg of the

page_text: rule itself. In this slide or slot, the carriage (B)-which may be made of metal or
any hard material-slides. On the other leg of the rule wo hinge by its end or ends,
the radial arm or arms, whilst the other end or ends engage in the above-mentioned
carriage (B).
In fig. (1) we illustrate our invention as applied to wooden rules. In Fig. 2 we
illustrate our invention as applied to steel or iron rules.
To use our invention the legs of the rule are pulled apart, until the radial arm or
arms (C) can be made to engage with the carriage (B), the legs of the rule are then
adjusted in relation to each other, until a line on the carriage (B) coincides with a
line on the slide or slot (A) indicating the angle required. This relates to wooden
rules and set squares. The same process is necessary with steel and iron rules, with
the exception that the radial arm or arms (U) is, or are permanently connected to the
carriage (B).
When our invention is applied to T squares Fig. 3, the radial arm or arms (C)
may be attached by its end or ends to the head of the T square-which must be of
the loose headed class-while the slide or slot (A) may be fixed to or cut in the blade
of the T square. The carriage (B), after being placed in the slide or slot (A) may
be connected to the radial arm or arms (C).
When our invention is used in place of set squares, we have two legs similar to
a two feet rule see Fig. (1), the radial arm or arms being as before, hinged at
the one end or ends, whilst the other end or ends, engage in the before mentioned
carriage (B).
When our invention is applied to levels, there is hinged to the level (D), a leg (E)
which carries the slide or slot (A) with its carriage (B); whilst, the radial arm.or.
arms are hinged to the level (D)."
Or, the level (D) may carry the slide or slot (A) with its carriage (B) whilst the
radial arm or arms may be hinged to the leg (E). See Fig. 4.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is,
The adaptation and application to rules, T squares, levels and set squares, of a
slide or slot, with carriage and radial arm or arms, for the purpose of indicating with
accuracy, different angles.
Dated this 13th day of May 1889