IMPROVEMENTS IN 'BACK SIGHTS FOR RIFLES
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by Samuel Hill at the Office of
the Commissioners of Patents, with his Petition, on the 15th
November 1875.
I, SAMUEL HILL, of Southwark, in the County of Surrey, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN 'BACK
SIGHTS FOR RIFLES," to be as follows:-
This Invention which relates to certain improvements in the "back
sights" of rifles, has for its object the provision of simple and effective
mechanical means adaptable to all existing and regulation flaps of
military or other rifles, and by the use of which in taking aim or sight
at an object, a due allowance in pointing or directing the barrel can be
accurately made for the effect exercised upon the projectile, by any wind
which at the time of firing may be blowing, so that if the firer be right
in his judgment of the apparent force of the wind he must necessarily
ensure a better aim and hit his mark.
The improvements constituting this Invention have especial reference
to an improved arrangement and combination of parts composing a
combined traversing or horizontal corrective sighting appliance, and

page_text: elevation or vertical sighting appliance, and to the combination thereof
with the ordinary flap.
According to the present improvements, and which are especially
adapted to the "Martini Henry" rifle, in the case of such rifle or of
any other in which the fore and back sights are at a similar distance
apart, each degree of the scale of the traversing sighting scale will be
computed and marked as to direct the barrel of the rifle three inches off
to the windward side of an object aimed directly at through the sighting
notch for every hundred yards of range; this three inches is not an
arbitrary but a convenient measure, it may be one, two, four, or more
inches, the principle of the improvement remaining the same. In this
improvement the object of the Invention can be arrived at according to
the following two modifications:-In the first of which the divisioning
of all scales might be alike, and in this case it would altogether depend
upon the distance between the fore and back sights of a rifle what
distance the barrel of the rifle would be directed off an object at every
hundred yards range, the results here being various in different kinds of
rifles, and in the second of which the divisioning of the scale would be
computed and marked according to the particular distance between the
aforesaid sights, and in this case the results in different kinds of rifles
would all agree, that is, for each degree, the barrel of each rifle though
it's divisioning were different would at cach hundred yards range point
one, two, three, or more inches off the object aimed at as desired.
The traversing sighting bar is made with an inverted V sighting notch,
which peculiar shape renders the sighting clearer, more distinct, and free
from blur or haze, and it is provided with depending internally tapped
lugs, through which passes a finely threaded screw which effects the
traversing of the sighting bar along the scale, and which is held by lugs
or sockets depending from a sliding bar, upon which the scale is marked
or to which when made separate it is or may be attached, and at each
extremity (so that it can be actuated by each hand, which is a great
desideratum) the said screw is provided with a milled or suitably formed
thumb nut; and these nuts are so placed in parts cut from the said
sliding bar as not to project beyond the extremities thereof, though in
such a position as to be most readily actuated.
The sliding bar is made to embrace the sides, back, and front, of the
flap in such a manner as to be capable of being adjusted up and down it
with precision, and as required.

page_text: It will thus be seen that the method of action of this improved and
combined vertical and horizontal or corrective sighting arrangement is
such that any allowance in pointing or directing the barrel of a rifle can
be accurately made immediately previous to firing to compensate for
the effect exercised upon the projectile by any wind which at the time
of firing may be blowing, such allowance depending in each instanco
upon the apparent force of the wind at the time.
I would here remark that I also obtain the objects of the Invention
in or according to the following modifications, that is, either by making
a portable or detachable scale, which can be placed when necessary
between the sides of the usual flap, and a pencil or other mark made
therefrom on the usual vertical sighting bar to show what allowance to
make and what part to aim from, or by making the scale upon the usual
vertical sighting bar itself.