Improved Means or Apparatus for Use in Looking Out or Taking Observations from Ships, Forts, Towers, or other Places.
Year: 1894

page_text: Date of Application, 21st Nov., 1894
Complete Specification Left, 23rd Sept.. 1895-Accepted, 16th Nov., 1895
Improved Means or Apparatus for Use in Looking Out or Taking
Observations from Ships, Forts, Towers, or other Places.
I, HENRY WEYBRIDGE FERRIS of 10 Lorne Gardens, Regent's Park in the
County of London, Gentleman, do hereby declare the nature of this invention to
be as follows:-
My invention has reference to means or apparatus for use in looking out or
taking observations from ships, forts, towers, or other places, and its purpose is to
enable objects to be observed notwithstanding the existence of obstacles or
obstructions in the direct line between such objects and the eye of the observer.
The invention mainly consists in the combination of one or more mirrors or
reflectors and one or more tubes the axis or axes of which are at an angle or
inclination to the mirror or mirrors, so that an object to be observed shall be
reflected by the mirror (or the first mirror when more than one are employed)
through the tube to the eye of the observer or to a second mirror and thence either
to the eye of the observer, or through another tube and thence to the eye of the
observer, or to a third mirror and thence to the eye of the observer, or successively
to any required number of mirrors and through any required number of tubes as
the circumstances of the particular case may necessitate according to the position
of the object to be observed or the look out to be kept, the position of the observer
and the intervening obstacles.
The mirror which is at the end of the tube or series of tubes nearest the object
to be observed, and which I call the receiving mirror, is preferably capable of being
turned in a horizontal plane at the will of the observer, so as to sweep any desired
part of the horizon; it is also preferably capable of being moved in a vertical
plane so as to be directed to and reflect objects that are either above or below the
horizon, as may be required.
Any suitable means may be adopted for giving these movements to the receiving
mirror. One convenient method is to mount the mirror on a vertical pivot and also
on horizontal pivots and to fit it with chains or the like extending to the vicinity
of the observer so that by working one chain or another he can adjust or move the
mirror either horizontally or vertically or both as he may desire. When the chains
or the like are long it is preferred to provide them with a spring compensator
for variations in length due to variations of temperature, so as to always keep
then taut.
A telescope may be placed at that end of the tube or series of tubes which
is nearest the eye of the observer, or lenses can be placed in one or more of the
tubes.
The apparatus is particularly adapted for use on board ship. It is known that
during a log at sea the atmosphere is often comparatively clear near the surface of
Advantage
the water while it is thick on a level with the deck, bridge or look-out.
of this fact can be taken by having a receiving mirror at the bow near the water
and a tube extending up from the mirror say to the level of the gunwale with or
without one or more other mirrors and tubes to reflect and carry the image to any
part required. Again, a receiving mirror at the masthead and a tube extending
therefrom down to the deck or other desired part will enable the captain or other

page_text: officer to obtain observations without a look-out man and even when in his cabin if
the mirrors and tubes are suitably disposed.
Dated this 21st day of November 1894.
J. C. MEW BURN & ELLIS,
55 and 56 Chancery Lane, London, Patent Agents.
Improved Means or Apparatus for Use in Looking Out or Taking
Observations from Ships, Forts, Towers, or other Places.
I, HENRY WEYBRIDGE FERRIS of 10 Lorue Gardens, Regent's Park in the
County of London, Gentleman, 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:-
My invention has reference to means or apparatus for use in looking out or taking
observations from ships, forts, towers or other places, and its purpose is to enable
objects to be observed notwithstanding the existence of obstacles or obstructions in
the direct line between such objects and the eye of the observer.
The invention mainly consists in the combination of one or more mirrors or
reflectors and one or more tubes, the axis or axes of which are at an angle or
inclination to the mirror or mirrors, so that an object to be observed shall be
reflected by the mirror (or the first mirror when more than one are employed)
through the tube to the eye of the observer or to a second mirror and thence either
to the eye of the observer, or through another tube and thence to the eye of the
observer or to a third mirror and thence to the eye of the observer or successively
to any required number of mirrors, and through any required number of tubes as
the circumstances of the particular case may necessitate according to the position
of the object to be observed or the look-out to be kept, the position of the observer
and the intervening obstacles.
The mirror which is at the end of the tube or series of tubes nearest the object
to be observed, and which I call the receiving mirror, is preferably capable of
being turned in a horizontal plane at the will of the observer, so as to sweep any
desired part of the horizon; it may also be made capable of being moved in
a vertical plane so as to be directed to and reflect objects that are either above or
'below the horizon. Any suitable means may be adopted for giving these movements
to the receiving mirror.
A telescope may be placed at that end of the tube or series of tubes which is
nearest the eye of the observer. Or lenses can be placed in one or more of the
tubes, in which case the tube or tubes in combination with one or more reflectors
constitute, optically speaking, a telescope, although the lenses may not all be in
the same axis and the object viewed is not in a line with the axis of any of the
tubes, as is the case with ordinary telescopes.
The apparatus is particularly adapted for use on board ship. It is known that
during a fog at sea the atmosphere is often comparatively clear near the surface of
the water, while it is thick on a level with the deck, bridge, or look-out. Advantage
of this fact can be taken by having a receiving mirror at the bow near the water
and a tube extending up from the mirror say to the level of the gunwale with or
without one or more other mirrors and tubes to reflect and carry the image to any
part required. Again a receiving mirror may be placed at a greater or less height
above the level of the deck or bridge and one or more tubes may extend therefrom
down to the bridge or deck or other desired part thus enabling the captain or other
officer to take observations from a level where his view would otherwise be more or
less obstructed by surrounding objects, and also enabling him to make use of a

page_text: telescope in conjunction with the apparatus, so as to command a view of any or
every part of the horizon; which telescope may, in some cases, remain fixed, or may
need only slight adjustment of its position.
The accompanying drawings will serve to show how my invention can be carried
into effect:
Figure 1 is an elevation and Figure 2 a plan illustrating how the apparatus can
be conveniently applied at the bow of a vessel for keeping a look-out during
a fog when the atmosphere is comparatively clear near the surface of the water.
Figure 3 is an elevation partly in section and Figure 4 a section on the line 44
of Figure 3, illustrating how the apparatus can conveniently be applied for keeping
a look-out or taking observations with the aid of a reflector situated at a greater or
less height above the level of the deck. In this apparatus a comparatively small
telescope is shown as fitted into the horizontal tube so as to turn with the reflectors
in a horizontal plane.
Figure 5 is an elevation of an apparatus also adapted for keeping a look-out or
taking observations with the aid of a reflector at a greater or less beight above the
level of the deck. This apparatus comprises a comparatively large telescope which
does not move with the reflectors. Figure 6 is an elevation of part of the apparatus
as seen when looking in the direction of the arrow 6 in Figure 5.
Figure 7 illustrates in elevation apparatus similar to that shown in Figure 3
except that the lenses of the telescope are fitted in the vertical tube.
Figures 8, 9 and 10 illustrate an arrangement adapted for taking observations
either straight ahead or straight astern or at any desired angle on either the port
or starboard beam.
Referring first to Figures 1 and 2, a represents the bow of the vessel; bis
a vertical tube secured to the bow by means of straps cc; other suitable means for
securing it may be substituted for these straps. d is a short tube extending
horizontally from the upper part of the tube b; the tube d should be at such
na height as to allow a person to conveniently look into it, and the lower end of
the tube 6 should be two or three feet more or less above the water level. e is
a mirror at the top of the tube baud f is another mirror below this tube and serving
as what I have hereinbefore called the receiving mirror. It will readily be under-
stood that the image or object which impinges upon the mirror will be reflected
up the tube b to the mirror e which in turn will reflect it through the tube d to
the eye of the observer. In order that it may sweep any desired part of the
horizon the mirror fis made capable of being turned in a horizontal plane. This
turning movement, according to the arrangement shown in the drawings is effected
by mounting the frame or support y of the mirror on a vertical pivot in the
form of an arbor h which passes through a bearing i and carries a toothed wheelj;
this wheel gears with a pinion k on a vertical rod 7 the upper end of which is fitted
with a hand wheel m within reach of the observer at the tube d. By turning the
hand wheel m in one direction or the other the mirror f' will turn on its pivot to the
extent or position desired. n is an index adjacent to the hand wheel' m to show
the extent of the movement, the hand wheel being marked with a scale.
Instead of the tube 6 being fitted outside the bow of the vessel as shown it
may be fitted inside the same, in which case there will be an aperture in the bow
opposite the mirror f. Or the tube may be inclined instead of being vertical
as shown in which case it will be fitted inside the bow, but its lower end will extend
to the outside. The diameter of the tube may be considerably varied and will
depend to some extent upon its length, but as a rule I consider about 9 inches
a suitable diameter.
Referring now to Figures 3 and 4, 6 represents the vertical tube as in Figures 1
and 2 and d the horizontal tube, f the receiving mirror and e the mirror at the
end of the tube where the tube d is situated. The tube d is placed at a con-
venient position for the observer above the deck or elsewhere and the tube b is
carried up to any required height. The mouth of the tube d is adapted to receive
a telescope such as p. The apparatus is carried by a vertical. pin or journal gl

page_text: which enters a bearing or suppport h¹; this bearing has a cog wheel i¹ with which
gears a pinion ¹ carried by the tube d. By turning the pinion ¹ by means of the
handle the whole apparatus can be turned axially in either direction on the
pivot g'. In order to provide for moving the mirror fin a vertical plane as well as
in a horizontal plane, I connect thereto one end of an arm the other end of
which is connected to the upper end of a rod m'; this rod is formed as a rack at
its lower end and gears with a pinion n¹ upon a shaft fitted with a hand wheel q
for turning it within reach of the observer." r is an index adjacent to this hand
wheel to show the extent of the movement.
p
is
In the apparatus shown in Figures 5 and 6 a comparatively large telescope
employed which does not move with reflectors and the vertical tube does not
rotate. The receiving mirror fis carried by a cap g which fits upon the open upper
end of the tube b and is free to turn axially thereon. For this purpose the cap
carries a toothed wheel which gears with a pinion on the upper end of a rod 1.
As the rod is not within convenient reach of the observer it is connected by bevel
gearing with a horizontal rod r which carries the hand wheel m.
q
The rod ris
supported by a fixed frame or brackets s. The wheel m is marked with a scale
to indicate the number of points the mirror fis moved to port or starboard. n is
the index. Inasmuch as the mirror e does not move with the mirror f the image
reflected by the mirror f when moved out of parallelism with the mirror e will not
be received and reflected by the mirror e in a vertical position. I therefore add an
erecting or correcting mirror v which is carried by a tube w fitted in the tube d.
The tube w carries a toothed wheel gearing with a pinion y which in turn gears
with another pinion on the rod r. Consequently as the mirror f is moved in a
horizontal plane by the turning of the rod r, the tube to also turns on its axis
together with the erecting mirror v. The relation of the gearing that turns the
tube w to the gearing that turns the mirror is such that the tube w turns just half
the distance of the mirror f. The mirror v is therefore always in position to erect
the image which appears in the mirror e the image then appears vertical in mirror v
and this vertical image can be seen obliquely in v by a small adjustment in the
position of the telescope. The figures show the mirror in the vertical position
which is the position it occupies when the mirrors e and fare parallel, with each
other no erecting of the image being then required. The telescope p is mounted
on a universal joint at A and its height at the observer's end and consequent angle
of observation can be adjusted as desired by means of the screw at B.
The apparatus shown in Figure 7 is the same as that shown in Figure 3 except
that the lenses of the telescope are placed in the vertical tube b, p being merely the
eye piece.
The apparatus shown in Figures 8, 9 and 10 is intended for taking observations
either straight ahead or straight astern or at any desired angle on either the port
or starboard beam. The reflecting mirror f is hung on a pivot at or near its
central axis and is brought into the required position by the handle f³ by means of
the chain; the lower mirror e is also pivoted at e2, and between these two mirrors
is a vertical mirror e in the tube b which is of square or oblong form. For looking
out straight ahead the mirrors e and foccupy the positions shown in Figure 8 that
is to say they are at an angle of 45° to the horizou. The mirror f then reflects the
image to the mirror e which in turn reflects it in the proper or erect position to the
tube or telescope at p. When however it is required to look out straight astern
the mirror must be moved over to the opposite side of the tube as seen in
Figure 9; but if it now reflected the image directly to the mirror e the image
would be inverted. The mirror is therefore adjusted at such an angle say
about 35° to the horizon that it will reflect the image upon the vertical mirror e³
which in turn. reflects it upon the mirror e. The inversion of the image is thus
obviated or corrected. The mirror e should be moved as required by means of
the adjusting device el to the same angle as the mirror f. In lieu of the vertical
mirror in the tube a similar vertical mirror can be substituted on the side
immediately opposite. This last mentioned mirror serves the same object as the

page_text: mirror the reflecting mirror must however then be adjusted to a larger
angle with the horizon so as to reflect upon the vertical mirror; this will at
times be found more convenient. If this arrangement be used the lower mirror e
would require adjustment in a corresponding manner.
It may be found more convenient in some cases not to have to alter the angle
of the mirrors e and f when an observation is taken astern. If the angle of the
mirrors remain at 45° no use will be made of the vertical mirror; but the image
in the mirror e will be inverted. I correct this by using a telescope in which
suitable inverting lenses can be inserted, removed or interchanged at the will of
the observer, as is done in those telescopes which are used at pleasure for
astronomical or terrestrial purposes.
For the purpose of taking observations at an angle on either the port or starboard
side I bring into use two external oblong double faced mirrors A. A. one ahead
and one astern of the box tube b. The mirror A is mounted in a suitable frame
swivelled at B on a rod C so that its near extremity can be placed near to and
on one side of the mirror f. Its further extremity is provided with a pin or
projection D which slides in a groove in the bar E. The mirror A is brought into
the required position by means of the hand wheel F and the handle G which should
be close to the observer. Thus the mirror A can be placed at any angle with the
longitudinal axis of the ship. When it is desired to make an observation directly
on the port or starboard beam the mirror is placed at an angle of 45° with such
axis. For any observation within the range of 90° between the bow and beam it
is shifted until it reflects the desired object to the mirror f. The mirror will
then reflect this object to the mirror e which again will reflect it through
the telescope p or otherwise to the eye of the observer in the same way as
for observations taken directly ahead. Observations may be taken abaft the
beam, i.e. between the beam and stern in a similar manner, except that the
mirrors and will be adjusted as previously described for observations made
directly astern.
The handle G when the instrument is being used should be kept in one of its
two extreme positions. The rod H is preferably operated by the hand wheel F
through geared wheel K as the mirror A requires fine adjustment. If it should be
desired to know the angle of the mirror A an index can be provided on the geared
wheel K. The mirror A A is turned by means of the hand wheel F and the
handle G on one side and parallel to the ships axis when not required to be used.
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 in respect of means or apparatus for use in looking out or taking
observations from ships, forts, towers or other places is :-
1. The combination of one or more mirrors or reflectors and one or more tubes
the axis or axes of which are at an angle or inclination to the mirror or mirrors, so
that an image or object that impinges upon the first or receiving mirror is reflected
through the tube or tubes to the eye of the observer, substantially as herein before
described.
2. The combination with an arrangement of mirror or mirrors and tube or tubes
such as referred to in Claim 1, of means whereby the first or receiving mirror can
be moved in a horizontal plane, substantially as and for the purpose hereinbefore
described.
3. The combination with an arrangement of mirror or mirrors and tube or tubes
such as referred to in Claim 1, of means whereby the first or receiving mirror
can be moved in a vertical plane substantially as and for the purpose herein before
described.
4. The combination with an arrangement of mirror or mirrors and tube or tubes
such as referred to in Claim 1 of an external receiving mirror capable of being
moved in a horizontal plane substantially as and for the purpose hereinbefore
described.

page_text: 5. The combination with an arrangement of mirror or mirrors and tube or tubes
such as referred to in Claim 1, of a telescope, or of lenses placed in one or more of
the tubes, substantially as and for the purpose herein before described.
6. The apparatus substantially as herein before described with reference to
Figures 1 and 2 for enabling a look-out or an observation to be taken during
a fog by means of a receiving mirror situated near the water.
7. The several apparatus substantially as herein before described with reference
respectively to Figures 3 and 4, Figures 5 and 6, Figure 7 and Figures 8, 9 and 10
for enabling a look-out or observation to be taken by means of a receiving mirror
situated at some distance from or above the mirror.
Dated this 23rd day of September 1895.
J. C. MEWBURN & ELLIS,
55 and 56 Chancery Lane, London, Chartered Patent Agents.