AN IMPROVED DIAL SIGHTING SCALE FOR MEASURING AND REGULATING THE SIGHTING ELEVATIONS OF RIFLES
Year: 1878

page_text: LETTERS PATENT to Herbert Porcy Miller, of 15, Craven Terrace, Hyde Park,
in the County of Middlesex, for the Invention of "AN IMPROVED DIAL
SIGHTING SCALE FOR MEASURING AND REGULATING THE SIGHTING ELEVATIONS
OF RIFLES."
Sealed the 18th October 1878, and dated the 15th May 1878.
PROVISIONAL SPECIFICATION left by the said Herbert Percy Miller at the
Office of the Commissioners of Patents on the 15th May 1878.
HERBERT PERCY MILLER, of 15, Craven Terrace, Hyde Park, in the County
of Middlesex. "AN IMPROVED DIAL SIGHTING SCALE FOR MEASURING AND
REGULATING THE SIGHTING ELEVATIONS OF RIFLES."
The novelty of this Invention consists in taking the readings from a revolving
dial instead of Vernier's system now generally in use.
The dial, which is placed on the top of the regulating screw, is of an inch in
diameter, and divided into ten equal parts.
The screw is made to travel exactly one inch in ten turns, and passes through a
slide, marking upon two uprights. The dial is attached to the screw, and made to
revolve under an index point fixed to the uprights, so that when the dial is moved
under the point from one division to another the screw raises or depresses the slide
according to the way the dial is turned, and from the slide the measurement is
taken.
Another advantage of my Invention consists in being able to use the instrument
for both Martini-Henry and Snider rifles. This is accomplished by allowing on the
back and front of the slide the difference in the elevations of the two rifles, so that
one side may be used for the Martini and the other for the Snider.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Herbert Percy Miller in the Great Seal Patent Office on the 15th
November 1878.
HERBERT PERCY MILLER, of 15, Craven Terrace, Hyde Park, in the County
of Middlesex. "AN IMPROVED DIAL SIGHTING SCALE FOR MEASURING AND
REGULATING THE SIGHTING ELEVATIONS OF RIFLES."
The novelty of my Invention consists in taking the readings from a revolving
dial, by which a hundredth part of an inch is magnified into an eighth, and thus
enabling the operator to easily measure the hundredth or even the four-hundredth
part of an inch without the aid of a magnifying glass.
The Invention will be clearly understood by reference to the annexed Drawings
in connection with the following description:-The instrument is composed of a
dial a, screw b, slide c, and a pair of uprights d, d; the dial is eleven-sixteenths of
an inch in diameter, the face being figured, and divided into ten equal parts, the
starting point being indicated by an arrow. For facility in reading, the divisional
lines are carried over on to the edge of the dial.
The screw has exactly ten threads or turns to the inch, and one end is passed
through the shoulder e of the uprights and fixed to the dial, the other or screw end
passes through the movable slide c. On the shoulder is fixed an index point f
and as the dial is moved under this point from one division to another, so the slide
is moved exactly the hundredth part of an inch; one complete revolution of the
dial will move the slide the tenth part of an inch. A half turn between any of
the divisions on the dial will give the two-hundredth part of an inch, and a quarter
turn the four-hundredth.
The studs M, M, on the slide are intended to take the sights of the Martini-
Heury rifle, and the ledge S, S, those of the Snider.
The elevation of the Martini-Henry rifle is just twenty-hundredths (4th) of an inch
lower than the Snider; this difference is allowed for between the knife edge over
the letter "S" on slide and corner of shoulder over the letter "M," so that the
knife edge is the guide to side scale g when using the Snider, and the corner over
the letter M" when using the Martini. This arrangement enables the same
instrument to be used for both rifles.
In using my Invention for the Snider rifle it is necessary to turn the dial until
the knife edge over the letter "S" (Snider) rosts under the first line on the side
scale, the arrow on the dial will then be under the index point. Now turn the
'dial from left to right, and thus place Figure "1" under the point, you will then
have one degree (or hundredth) of elevation; if on to Figure "2," two degrees, so
that when the dial has been once round ten degrees will be recorded. The knife
'edge will then rest over the first division of ten on the side scale. If, say, seven-
teen degrees are wanted, go on turning the dial until " 7 comes under the point,
the elevation will then be seventeen-ten on the side scale and seven on the dial; the
side scale giving the tens and the dial the units.
"
For the Martini-Henry rifle the operation is the same as for the Snider, with the
exception that the point of shoulder over the letter "M" (Martini) will be the
guide for the side scale instead of the letter "S.”
In witness whereof, I, the said Herbert Percy Miller, have hereunto set my
hand and seal, this Thirteenth day of November, One thousand eight
hundred and seventy-eight.