IMPROVEMENTS IN APPARATUS FOR WEIGHING LETTERS AND OTHER ARTICLES
Year: 1869

page_text: PROVISIONAL SPECIFICATION left by Nathaniel Richard Hall at the
Office of the Commissioners of Patents, with his Petition, on the
9th June 1869.
I, NATHANIEL RICHARD HALL, of Rosherville, in the County of Kent,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN APPARATUS FOR WEIGHING LETTERS AND OTHER ARTICLES," to be as
follows:-
My Invention relates to an improved construction of apparatus for
weighing letters and other articles, by which I am enabled to ascertain
the weight (and also, if desired, the charge for postage) of much heavier
letters or packets than has hitherto been practicable without the aid of
counterweights or springs.
Heretofore, in balances in which neither counterweights nor springs
are employed, it has been impossible to ascertain the weight of a letter
or article beyond four ounces with accuracy; but by means of the
improved apparatus of my Invention the weight of letters or other
articles may be determined from less than one quarter of an ounce to
sixteen ounces, more or less, if desired.

page_text: My improved apparatus consists of a flat bar or beam of metal or
other material of suitable dimensions. Upon this beam is fitted a
sliding piece capable of being placed in any position on said beam; this
sliding piece which may be fitted in any suitable manner so as to slide
with slight friction on the beam, is furnished with a hand hold or
pendant jointed thereto, and thus forms a movable fulcrum for said
beam, being adjustable in position thereon. This sliding piece is placed
more or less distant from the centre of the balance beam, according to
the weight of the article. The article to be weighed is suspended from
a clip or other contrivance suitably connected to a link jointed to the
end of the balance near its upper edge, so as to swing freely thereon to
a limited extent. When the beam is suspended horizontally the link
hangs vertically thereon, and coincides with a line marked on the face
of the balance at one end, by means of which the horizontality of said
balance is determined in all the various positions of the sliding piece.
A graduated scale or scales are marked on the face of the balance from
the centre to the end from which the article is suspended, with one or
other of which lines the edge of the sliding piece is made to coincide as
before mentioned by sliding it along the balance until the latter (having
the letter or other article attached) assumes a horizontal position on
being suspended by the pendant. The weight of the letter or article is
indicated by the figure or figures annexed to the mark with which the
sliding piece coincides. A second scale indicates simultaneously the
amount of money required for the postage, or (if used for articles sold by
weight) the price of the same. In weighing a light article, the sliding
piece or movable fulcrum would be placed towards the centre of the
balance, so as to nearly equalize the two ends of the same when sus-
pended by the pendant; and in weighing a heavy article the sliding piece
is moved towards the end from which such article is suspended, until the
balance attains a horizontal position, as before described.