Year: 1898

page_text: EDWIN JAMES CARTER, 2, Harriet Terrace, Queen's Road, Everton, Liverpool,
Master Mariner, do hereby declare the nature of this invention to be as follows:
My invention is for taking altitudes by looking directly at the object required,
immaterial of fog, thick weather, or horizon so long as the object is in view.
It consists of an arm (of bell shape crank) placed parallel to the plain of the
sextant by a pin in the centre of the crank (called the main pin) having the upper
& lower arms of a free pendulum motion, weighted at the lower end to keep its
perpendicularity, at the top end is a fine needle, placed at right angles to the
crank, so fixed on a slotted small bar to slide freely by a screw for adjusting
purposes the bottom end of the arm is a weight.
The main pin has a screw thread on the lower part, & is fixed exactly on a
centre line, from the axis of the sextant to 0 of the nonius, by screwing it into
the index bar, directly below the index glass, leaving the crank free motion. On
the other end or top is a screw thread with a small thumb screw, for tightening a
ferrule that is placed over this pin, this ferrule being flanged on the lower end, &
a screw thread with screw on top for compressing purposes, there also being on
this ferrule two light springs (of material that will not rust) between these is
placed, flanged at both ends, the crank ferrule whose motion is regulated by
the compressing screw, so acting on the springs, that it may have a smooth &
regular pendulum motion, if the observer happen to be, say, in a vessel that is
in a heavy sea way.
I also place a small stationary pin (similar to the index pin in thickness) on
the horizon glass, about half way up on the mirrored part, in front. Then by
the raising the sextant get the limb of the object required on this pin, & looking
through the sight tube, (this action throws the index pin of the line of sight) &
by moving the index bar forward until the reflected index & horizon pins coincide
into one straight line, which when read of on the are will be the altitude required.
I have also applied a pawl on the lever in such a way, that it will be locked,
whilst holding the sextant horizontal, also preventing it from injury by the
weight swinging unnecessarly.
The adjustment of the index pin is regulated by a screw, attached for the purpose
This idea may be used at night for observing star, planets &c. by simply
coating the index & horizon pins with luminous paint. I may decorate, & beautify
but in no way shall detract from the above description.
Dated this Seventeenth day of March 1898.

page_text: An Improved Attachment for Sextants.
EDWIN JAMES CARTER, 2, Harriet Terrace, Queen's Road, Everton, Liverpool,
Master Mariner, do hereby declare the nature of this invention and in what man-
ner the same is to be performed, to be particularly described and ascertained in
and by the following statement:-
This invention has for its object, the taking of altitudes in thick or foggy
weather, so long as the object to be taken is visible, by making the object
my horizon. This improvement I have called the "zenometer" on account of
the angle being measured from the zenith; and it can be better described by the
aid of the accompanying drawings, in which:
A perspective view, giving a general view of a sextant with the im-
This attachment
Fig. 4 parallel to
lower end
ferrule B,
the
a
Fig. 1.
provements.
Fig. 2 to 10. Detail views in perspective, (enlarged).
Fig. 11.
A side elevation of the upper part of the sextant.
consists of an arm or bell crank lever A working on a pin a.
the plane of the sextant; it has a pendulum motion;
of this crank or arm A, has a weight a and midway
which fits on the same pin a, and has points b on the inner
upper side, and also a lug of conical shape 1, placed on the top of the
ferrule B; the top part of the crank A is made at such an angle, that it strikes
a supposed line (called the reflected sight line), and drawn exactly from the centre
of the horizon glass, to the centre of the index glass, at an angle of 90 degs.; on
this end of the crank is placed a travelling, or index pin C, which can be adjusted
by a screw, running across the end of the crank A, so as to make it cut the line
above mentioned, (if casting be incorrect). On the same pin as the crank A, I
place a second weighted arm 1), which has on its top a ferrule d, abutting the
ferrule B, on crank A, but working independently of it; on the outside of the
ferrule d, a fixed spring is placed, the free end being forked d', which engages
with the conical lug 6, (as shown in Figs. 1, 2, 3, and 11); on the outside of the
ferrule d, is a screw thread (partly its own length) with a groove on its upper
surface, (not shown in the drawing) for holding the spring when compressed, this
spring working on the conical lug 6', envelopes it on three sides, and is worked
by a travelling nut, E, on the thread of the ferrule d, so compressing or casing
according to the motion or vibration of the ship, this ferrule d, with the weighted
arm D, has a free pendulum motion, thus counteracting the motion of arm A,
in cases of great movements, also giving greater accuracy of the zero's position
of the pin C. These ferrules B and d are secured on to the pin a by a small screw
nut (Figs. 1, 4, and 11). The pin a is screwed into a brass block working in
a slot in the quadrant piece F, this piece F, I place between the horizon and index
glasses, and is connected to the sextant by a screw G, with a milled head g, as
shown in Fig. 5; the lower part of this quadrant piece F, has serrations f, with
which a pawl 63 (Figs. 2 and 11) on the crank A, can be engaged, its use being
to prevent the weighted arm A, from swinging about whilst handling or reading
the sextant's arc.
On the lower part of the pin a is a bar H, (Figs. 4 6, and 11) connecting with
the index bar H¹, and fixed on a movable adjustment h (Figs. 8 and 11), and
secured to it by a thumb-screw S, (Figs. 7 and 11), on a line from the centre of
the index plate. The position of the pin a being regulated by the bar H, in the
slotted quadrant F, by the index bar when moved.
The horizon pin J, (Figs. 1, 9, and 11) is screwed into a sliding block K, that

page_text: is moved by an adjusting screw K¹, parallel to the plane of the sextant as required;
this adjustment is fitted on to the back of the frame of the horizon glass M.
The telescope L, that fits in the tube ring, is reduced from the said ring so as
to allow a free passage between the weighted arms A, and D.
All the pins have grooves in them, the horizon pin J, the index pin (', for to
allow luminous paint to be inserted for night observations. These grooves are so
arranged, that the paint will throw a clear and defined luminous line.
All the adjusting screws are capstan or milled headed to prevent too easy
handling. (Fig. 10).
The mode of action is as follows:-To adjust this attachment, draw a line
level with the eye (for the horizon line) look through the telescope L, and adjust
the upper part of the horizon pin J, to touch the lower part of the reflected index
pin C. Then take the altitude of an object by the sextant, say 30 degs. leaving
the index bar H', clamped, raise the sextant, look through the telescope and
placing the horizon pin J, to the object to be taken, then if the angle is too
great, the horizon pin is too low; unclamp the index bar H', and take the altitude
of another object say at 18 degs. Proceed again as described above, and adjust
so on alternately until the instrument is correct.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is-
1st. An improvement attached to sextants whereby the altitude of the sun,
moon, or stars can be taken in foggy weather (if the object is visible,) by raising
the sextant, and looking directly at the object, as substantially shown and
described.
2nd. Having a lever or levers (one of the bell crank shape) which acts as a
pendulum motion, being weighted at one end, and having an index pin or
travelling pin, and on the other a compressive forked spring, as shown and
described herein.
3rd. The combination of weighted levers, also the attachments for moving the
sliding pins, as herein as before described and illustrated in the accompanying
drawings.
Dated this 15th day of March 1899.
EDWIN JAMES CARTER.
Applicant.