IMPROVEMENTS IN INCANDESCENT LAMPS AND IN APPARATUS EMPLOYED IN CONJUNCTION THEREWITH
Year: 1883

page_text: LETTERS PATENT to Otway Edward Woodhouse and Frederick Lawrence
Rawson of Queen Victoria Street in the City of London and Walter Harris
Coffin of South Kensington in the County of Middlesex for an Invention
of IMPROVEMENTS IN INCANDESCENT LAMPS AND IN APPARATUS EMPLOYED IN
CONJUNCTION THEREWITH
i
PROVISIONAL SPECIFICATION left by the said Otway Edward Woodhouse,
Frederick Lawrence Rawson, and Walter Harris Coffin at the Office of the
Commissioners of Patents on the 16th February 1883.
OTWAY EDWARD WOODHOUSE and FREDERICK LAWRENCE RAWSON of Queen
Victoria Street in the City of London and WALTER HARRIS COFFIN of South
Kensington in the County of Middlesex "IMPROVEMENTS IN INCANDESCENT
LAMPS AND IN APPARATUS EMPLOYED IN CONJUNCTION THEREWITH"
This invention relates to a special form of electric lamp particularly adapted for
surgical, microscopical and other scientific purposes, as also to certain apparatus
adapted to be used in conjunction with incandescent lamps, all as hereinafter set
forth. The lamp according to this invention may be either perforated with one or
more holes or apertures to be looked through, or may be of annular, horse-shoe,
"looped, or other closed or partially closed form which shall permit open or clear
spaces to be left for the sight and around or. partially around which perforations,
apertures, or spaces, the incandescent filament or filaments shall be placed. Or in
some cases an incandescent filament alone of suitable material and with a central
space to be looked through may be used. Said filaments may be formed of wire,
carbon or other suitable material, and rendered incandescent by electric current or
discharge
The lamp or filament may be provided with an opaque screen or screens, reflective
or non reflective as required, perforated or otherwise so disposed as to hide the
light from the eye when looking through or between the filament or filaments or

page_text: for the same purpose a portion of the lamp may be made of opaque material or be
coated with paint or otherwise obscured When a reflective surface is employed it
is preferably so disposed as to concentrate the light either immediately around the
sight aperture or otherwise, according to the angle or obliquity of illumination
required, and project it either with or without supplementary lenses in a hollow
beam parallel, divergent or convergent as desired Lamps so constructed may be
mounted in various forms as eyeglasses, hand lenses or spectacles
When a lamp or filament is attached to a handle, holder or socket, for purposes
where in order to conveniently incline or adjust it in relation thereto a swivel or
hinge joint connection is required, this is preferably accomplished by swivelling,
pivoting, or hinging it, or its reflector, case. or mounting upon its two electrodes
themselves, whereby electrical contact is conveniently maintained, without
restraining its motion-and for this purpose the electrodes of the lamp or filament
may terminate in two pins, pivots or tubes in the same straight line working in
suitable holes or bearings in the electrodes or conductors of the handle, holder, or
socket, or vice-versa or the electrodes of the lamp may be led into two depressions
in the glass or onto two elevations upon it and articulating with corresponding
"centres" journals holes or bearings respectively in the electrodes or conductors of
the handle holder or socket In 'these cases, contact may be maintained by the
springy construction of the electrodes of either the handle holder or socket or of the
lamp or filament or by a set screw device
Also for the same purpose, the electrodes of the lamp or filament may terminate
as a pin or pivot and a surrounding concentric ring or tube respectively or in two
concentric rings or tubes fitting into and turning upon similar tubes forming the
electrodes of the handle holder or socket-or vise versa One or both pair of such
electrodes may be split or made conical for frictional contact, which also as above
may be maintained by either springy construction or by set screw
In any case the adjustment or restraint of the movement of the lamp or filament
upon such hinge or joint may be by friction only, set screw or other clamping
device, or may be controlled, by a rod slide or other usual mechanism upon the
handle, holder or socket
The above details of mounting and connecting the lamps as also the arrange-
ments and devices for cooling and protecting them, hereinafter described, are equally
adapted for use with the ordinary form of incandescent lamps now employed as
also for galvanic cauteries as will be apparent from the following description Great
difficulty has been experienced in keeping incandescent lamps externally cool, where
as in surgical operations and other special purposes, this is particularly desirable
and to secure this end, a portion of the lamp itself or its screen or screens reflector
mounting or case is made with a largely increased extension of surface to facilitate
its parting with heat to any liquid or gas in contact with it. For use in air only,
or when entirely submerged in a liquid this is attained by crinkling, corrugating or
otherwise simply increasing the surfaces above mentioned but as it is also desirable
to take advantage of the cooling effect of evaporation, the increased surface is
preferably made also absorbent so as to take up and retain a liquid by capillary
attraction
To this end there is attached to the glass by melting, cement or otherwise or to
the screens or reflector mounting or casing a felted mass of spun glass, silicate wool,
asbestos wire gauze, coils or a reticulated network of wire, spongy metal or a brush
like arrangement of fibres preferably of a metallic good heat conducting material,
or a covering of any textile or other absorbent fabric may be used or a combination
of any of the above as convenient A lamp so constructed may for some purposes,
be wet from time to time in any way, or in other cases, as certain surgical operations
will absorb the natural fluids of the parts it comes in contact with and moreover
will sometimes be further cooled by the forced evaporation caused by the breath-
but in order at other times to produce these effects a stream of air, or of water or
other cooling mechanism, or both may by arrangements hereinafter described be
“directed upon the lamp or its accessories

page_text: Or the current or currents of the cooling medium may be similarly led into a jacket
or casing partly or wholly enclosing the lamp or its accessories Such jacket may
communicate with the exterior by one or more openings or perforations, for the more
or less gradual exudation of the cooling medium or be entirely enclosed for the
circulation of the cooling media within and to and from it It is preferably made
of metallic or other good heat conducting material with suitable partitions or
baffling plates, for thorough circulation and may be internally roughened or corru-
gated to facilitate cooling or filled with subdivided material preferably metallic, as
wire gauze, coils, shot and the like for the same purpose To supply the lamp or
its jacket with the gas or liquid and carry it away if necessary, it is preferred to
make the electric conductors whether constituting the handle or holder themselves,
or part of, or separate from it and the electrodes of the lamp where necessary,
hollow for the whole or portion of their length, for the conveyance of both electricity
and the cooling media They may be preferably concentric tubes one within the
other or separate ones, with suitable socket joints where necessary and either rigidly
attached to the lamp or jacket or connected to it by hollow electrodes pivotting or
swivelling as previously described This arrangement not only provides a compact
and simple construction, but by cooling the conductors and reducing their electric
resistance increases the current strength and adds to the efficiency of the lamp.
For the same purpose the conductors may instead be enclosed in a tube or tubes,
or a combination of these means be employed
The lamp or its accessories may be further provided with asbestos felt or other
heat non conducting shields where necessary
In incandescent lamps, as also in electric cauteries when used with certain
batteries of high initial potential, the greatest danger of injury to the filament
occurs when the current is first passed through it and to avoid this evil, the handle
holder or socket or switch or commutator used with the lamp may advantageously
be provided with a sliding or other contact key so constructed that the current
cannot pass through the filament without first short circuiting the battery
In order to protect the glass of the lamp where the connections are sealed in, the
end of the neck nearest the seal is heated and the connections pushed in toward
the bulb, or the air may be exhausted and the seal in that manner be drawn into
the neck The lamp may be held securely in place and good electrical contact
obtained by providing the holder or lamp with spring prongs bearing upon the bulb
of the body of the lamp or upon the holder as the case may be Furthermore in
order that the lamp may fit well and be interchangeable with others in the same
socket handle or holder, the neck of the lamp may be pressed or moulded to a
definite shape or form

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Otway Edward Woodhouse, Frederick Lawrence Rawson, and
Walter Harris Coffin in the Great Seal Patent Office on the 16th August 1883.
OTWAY EDWARD WOODHOUSE and FREDERICK LAWRENCE RAWSON of Queen
Victoria Street in the City of London and WALTER HARRIS COFFIN of South
Kensington in the County of Middlesex ** IMPROVEMENTS IN INCANDESCENT
LAMPS, AND IN APPARATUS EMPLOYED IN CONJUNCTION THEREWITH
"J
This invention relates to special forms of electric lamps, particularly adapted for
surgical, microscopical and other scientific, as well as general purposes-as also to
certain apparatus and accessories adapted to be used in conjunction therewith, all
as hereinafter set forth. In order to more clearly describe the nature of the said
invention reference is made to the accompanying drawings where the particulars
and details of construction are fully illustrated and in which briefly Figure 1 is an
elevation of an incandescent lamp Figure 2 is a sectional view of the same with a
screen or reflector. Figure 3 the same with lenticular front to lamp. Figures 4.
5 and 6 show the same mounted in handles or holders, and combined with a lens.
Figures 7. 8. 9. 10. 11. 12 and 13 show other methods of forming special forms of
lamps and also of mounting or attaching incandescent lamps to handles or holders.
Figure 14 shows the same, and also a special switch or contact maker. Figures 15
and 16 show special means for keeping incandescent lamps, cool as well as another
method of attachment to a handle or holder Figures 17. 18 and 19 illustrate
special forms or constructions of incandescent lamps with method of mounting on
handles or holders and other arrangements for keeping them cool Figures 20. 21.
22. 23. 24 25. 26 and 27 show methods of enclosing incandescent lamps in cases or
jackets, to protect them and reflect and refract their light, with means of attaching
the lamps, cases, or jackets to hollow or tubular handles, holders, or conductors,
containing cooling media Figures 28. 29. 30 and 31 relate to details of reflective
and cooling jackets or cases, attached to or forming a part of the lamps Figure 32
is a special forn of lamp, as also a method of attaching one to a handle holder or
support. Figure 33 shows in clevation and two sections, a means of controlling
the relative movements of two parts of a handle or holder. Figure 34 gives in
elevation and section, methods of constructing a special form of resistance coil or
rheostat. Figure 35 is a section of a particular form of short circuiting or shunting
switch Figure 36 shows a method of mounting or holding a lamp in a holder or
socket Figures 37 and 38 are other forms of holders or sockets for the same
purpose Figure 39 illustrates a method of holding a lamp in any position by an
adjustable, flexible conducting support Figure 40 illustrates a particular form of
lenticular or prismatic walled flat lanp, and also details of special construction of
neck Figures 41 and 42 show special forms of rotating lamps mounted in tubular
or other handles or holders. Similar letters in most of the different figures
indicate similar or corresponding parts-all as hereafter more particularly set
forth and described. According to our invention, the lamp as in the generalized
form shown by Figure 1 may be either perforated as at a (and in section shewn in
Figures 1 and 2) at Z with one or more holes or apertures, around or partially around
which the incandescing filament for filaments shall pass, or may be of horseshoe,
looped, spiral, "figure of eight" or any other closed or partially closed form, leaving
clear open spaces around or partially around which the filament or filaments are
arranged. The objects of this construction are two fold, firstly in order that when
used for certain purposes, by looking through a hole, aperture or open space, the whole

page_text: length of the filament or filaments, may be as nearly as possible in the line of
sight; and secondly; that a flat general form of lamp (more convenient for some
purposes than globular or spherical, as when used with reflectors and lenses) may
be of more nearly circular and therefore strong and symmetrical cross section
When these particular objects are not in view, a lamp for ordinary purposes, may
according to this invention, be so made that its filament is everywhere equally
distant from the glass of the bulb which distance is morcover greater than the
maximum distance in a lamp of the ordinary construction having the same general
external dimensions, and furthermore such lamp will be more uniformly heated,
present a larger cooling surface, and be more conveniently and safely packed with
others than the usual shape of corresponding size and efficiency By our invention,
the external contour of the lamp and the apertures, perforations or partially
enclosed spaces may have any shape or figure whatever, but it is generally
preferable to have symmetrical curvature and uniform convexity which is best
attained by a regular annular or horseshoe outline and circular or elliptical cross
section In constructing a lamp, where as in Figure 1, the filament f nearly
surrounds the aperture a the filament attached to its full length conductors or
legs c c may be introduced into the bulb through an orifice left in the glass at x
(opposite the neck n) which is afterwards closed; or it may be introduced through
the neck n in the ordinary way before the aperture is made in the bulb, or it may
be attached to one full length conductor e only, and to a short one or to two short
ones, and be placed in position through the neck, after which one or both full length
conductors or legs may be fastened or attached to the short ones or other methods
of placing the filament or filaments, and their conductors in position according to
the shape and size of the lamp may be employed. The neck of the lamp n which
generally supports the conductors c c¹ and into which they are usually melted or
sealed, we prefer to pinch flat in the plane occupied by the conductors, and also to
press or mould to a definite shape or form. Moreover in order to protect the
sealing in of the conductors and to shorten the neck and the conductors, and for
other reasons, we sometimes heat and soften the neck near the seal and push the
neck and the connections in towards the bulb, or the air within may be partially
exhausted during the heating and the seal thereby drawn into the neck as shown
in section at n Figure 32. The lamp may for some purposes be provided with an
opaque screen or screens, perforated or otherwise disposed to either hide the light
from the eye or to reflect the light as required, or for both purposes combined as
shewn in Figs 2 and 3 where r r is the obscuring screen or reflector and Z Z the
lamp in section both being perforated at a when it is required to look through them.
When reflective any suitable optical figure may be given to the screen, according to
the use desired. Fig 2 shewing a form adapted to throw the light as a large
parallel beam and Fig 3 a shape for concentrating the light more immediately
around the sight aperture and projecting it in greater intensity, either convergent,
parallel, or divergent, as arranged, in which figure also, the glass of the lamp is
shown as thickened to a lenticular shape at q q. For the same purpose a portion
of the lamp may be constructed of or coated with an opaque material, reflective or
not as required, or obscured by the protective and cooling arrangements to be
described. The lamp with or without the above described screens or reflectors
may be combined with lenses, prisms, mirrors, and such optical means as are desirable
either attached to, or forming part of the lamp itself. Fig 6 shows a lamp / with
plain convex lens attached to a reflector r Fig 16, a lamp with special purpose
jacket reflector and double convex lens q and Fig 24 a lamp within a jacket closed
by glass or its equivalent at t forming a water lens q all hereafter further described.
The glass of a lamp may be thickened where a lenticular or prismatic refraction of
the light is required at at q in Figs 3. 8. 9. 42 or one or both sides of a flat lamp
may be formed of or blown into lenses as at q in Figs 40 and 11 or into annular or
other shaped "total reflection or other prisms as at j Fig 40. Lamps so constructed
and arranged may with advantage be applied to such instruments as ear, nose, or
vaginal speculae microscope objectives, used as opthalmoscopes, laryngoscopes, or
"

page_text: general surgical encloscopes, and mounted in various forms as band lenses or eye
glasses for jewellers, mechanicians, miners, divers &c, and similar philosophical or
industrial purposes
In some cases an incandescing filament only, of suitable
material, combined with a screen as described with or without other accessories
may be employed In attaching or mounting a lamp or filament, or its reflector
case, jacket or other accessories, upon a suitable handle, holder, socket or other
support, we prefer arrangements whereby the mechanical hold, the proper electrical
contacts and means for permitting, controlling and adjusting the movement and
position of one relatively to the other are attained by swivelling, pivoting, hinging,
socketing, sliding or clamping the electrodes, terminals or conductors of the one,
directly upon those of the other. In carrying out this the conductors c c¹ of
the lamp as in Fig 1 may be suitably bent, and for instance terminate as
at c. e or elsewhere, in either conical, cylindrical, tubular, spherical, or any figure
or surface of revolution or other suitable electrodes, directly upon the lamp itself
or its reflector, case jacket, mountings, fitting or accessories These two electrodes
may be related to each other in two ways or positions-firstly by both having
the same axis of revolution that is lying in or surrounding a straight line
around or along which the lamp will move and common also to both electrodes
on the conductors of the handle or holder, which therefore may be fixed
or secondly by having different axes or centre lines, parallel but side by side
when the corresponding electrodes, on the conductors of the handle or holder must
move in relation to each other that the lamp may turn on them. As instances
of the first type or single axis class Figs 4 and 6 shew a lamp 7 (such as in
Figure 1) swinging by its pivot shaped electrodes e e¹ in holes or bearings upon
the conductors k k which may constitute or be a part of the holder, handle, or
support H. Conversely, the lamp electrodes e e¹ may so terminate as to articulate
with pivots or pins upon the handle conductors k k Or the lamp conductors may
be led to surmount elevations or nipples or to occupy depressions as in Figure 5
upon the lamp itself, or its case and articulating suitably with k k³, or they may
simply terminate in cavities with circular orifices, to be filled with mercury, and
closed by stoppers on the handle conductors k k¹ Conversely, lamp electrodes may
stop mercury cavities in the handle or holder. A convenient form (among many
obvious modifications) is shown in Figures 15 and 16 where the straight lamp
conductors terminate as two parallel rings e e' each embraced on their inner aspect
by the holder H at hand on their outer sides and interiorly by cones y on the
conductors k k² of the handle H The lamp electrodes may be two tubes either
similar and in the same line working on wire pin or tubular conductors, or may be a
pin and tube or two tubes, one within the other fitting on similar or suitable handle
conductors, and in all the electrodes may be formed with their axis in any position
around which the lamp shail move-In the special case where a lamp is to be
revolved on its own centre or median line, the neck may very conveniently be made
cylindrical or conical and the electrodes two rings or tubes upon it, or a ring or tube
and a central pivot on the bottom of the neck and the conductors on or constituting
the handle may be concentric tubes as at k k', Figs 20 or 41 or a tube and
wire as in Figs 21 or 42 or may be only portions or segments of concentric tubes
or their equivalents. In Fig 41. the lamp is shown with its neck n reduced at the
end to fit the inner tube k', and in Figure 42 one electrode is central and
embraced by a split wire or other conductor k¹ The cylindrical or conical neck
may furthermore have one or two annular grooves, or flanges moulded upon it
when blown, to be engaged by suitable rings, cones, tubes plain or grooved or
.flanged or portions or segments of them In all these cases and in Figs 41 or 42,
the lamp conductors or electrodes may be simply led on to the surface of the glass
of the neck, when it is entirely embraced by the handle conductors or otherwise
may entirely surround it Any shaped neck may as at n Fig 40 have metallic
rings flanges or banda put on (or the necks may be blown into them) either below,
flush, or above the surface of the glass as shewn at e e, which metallic pieces may
⚫ be the electrodes and when cylindrical or circular be of either the same or different

page_text: diameters for socketing as above described Obviously the tubular or other
handles or holders may be perfectly straight or bent as in Figs 41. 42 or 20 or at
any other angle. Moreover those constructed as these figures may by means of
bent or curved cylindrical couplings or sleeve joints upon them as at C Figs 41
and 20 be readily altered to any desired shape or curvature A holder or support
to carry a lamp in any desired position may be made of one or more thick plain or
stranded wires of a suitable tin or other alloy which may be readily and repeatedly
bent to any shape or curvature, as shown in Fig 39 illustrating such a holder
composed of a thick central wire as one conductor and a fine wire k loosely
wrapped around it as the other, one or both of which may be insulated When it
may not be necessary to hold the lamp very firmly or to allow for great range or
freedom of motion between it and the holder, the lamp electrodes e e' as in Figs 10
and 11 may be simply hooked on to bent wire or other conductors upon a
handle or holder H and electrical contact can be maintained by making the handle
or holder H at least at that part nearest to the lamp, of the same size and shape
as the neck of the lamp or its case or covering, and encircling both with a
sufficiently thick but elastic tube or ligature of india rubber or its equivalent i
bearing preferably at each end upon projections or shoulders upon the lamp or its
case, and the handle or holder respectively; when its tendency to straighten after
any distortion may be so adjusted as to keep the electrodes in contact Or two
separate india rubber or equivalent tubes or ligatures may be used either as in
Figs 12 and 13 side by side where both the handle or holder and the neck of the
lamp or its case are shown as bifurcated or double for the tubes ii; or one inside
the other as shown in Fig 27 to be hereafter described In these two cases of
double tubes as in Figs 12 and 27, the electrical contact may be better secured by
placing mercury within the two cavities formed by the tubes at m m³ in which
the electrodes terminate, in which case it is not essential that the electrodes or
conductors of the lamp and the holder or handle respectively should hook onto or
be in contact with each other. When the electrodes and conductors hook onto
each other, as in Fig 10, the lamp may be more firmly and rigidly supported and
good electrical contact maintained, by three or more spring prongs, tongues, or
wires ppp Fig 14 attached to the handle or holder H, and bearing upon the body
of the bulb or case of the lamp or vice versa. Or for the same purpose, two or
more wire loops crossed as at L in Fig 38 may be used The said spring prongs,
tongues or loops may also be used in combination with spiral spring terminal
loops or hooks upon the holder as shewn in Figs 30. 37 and 38 at b When
as in Figure 36 a lamp is held which has its terminals or electrodes at the side and
higher up the neck, two of the prongs or tongues at opposite sides are made the
conductors and are provided with spurs or spikes as at g which by slightly rotating
the lamp engage with the looped terminals or electrodes of the lamp and in that way
the lamp is both secured and electrically connected, instead of by spiral spring or plain
hook terminals We are aware that various forms of prongs and crossed wires have
been used to support electric lamps, but they have not been arranged as and for the
purpose described and have extended only to the neck or lower portion of the bulb
and we do not claim these latter forms as we deem them imperfect. Fig 32
represents a hollow holder within which a piston T enables the wire conductors to
be pushed up against their own springy construction that the lamp may be hooked
or unhooked at the top. Or a combination of any or all of these means may be
employed. As an example of the other type of swivelling or method of providing
for the motion of the lamp by two axes Figs 7. 8 and 9 illustrate a method of
doing this, where the lamp conductors c. c' are so hent as to be parallel, not in the
same line but side by side (shown in plan looking at the bottom of the neck at P)
and terminating as pins or pivots ee working in sockets in the two separate
conductors of the halves constituting the handle H. As shown in Fig 9 the lamp
swings or inclines by the two parts of the handle or holder moving or sliding
lengthwise in relation to each other. Obviously the pins pivots or tubes may be
upon the handle conductors, working in bearings or sockets forming the electrodes

page_text: on the lamp or its case as in Figs 25 and 26 hereafter alluded to. Or the neck of
the lamp or its case may on each longer face have either a groove as in Fig 19 at
e e' or an elevation ridge or edge as at e e¹ Fig 18 formed upon it, which may be
themselves the lamp electrodes or have the conductors led to and terminate in or
upon them, one on each side or face, such forinations articulating with suitable
edges or grooves upon the two conductors of the handle or holder HH' as illus-
trated. In all the above described and similar pivoting devices, we can protect the
joint by a box bulb band, tube or ligature of india-rubber or its equivalent, put
over the junction as illustrated in Figs 15 and 16 at i The motion may be
restrained by friction at the bearings caused by stiff or springy construction of the
conductors or electrodes, by the encircling rubber or other ligatures and other ways
or by set screw, clamping and similar devices; but in those of the first style or
single axis, we prefer to control and adjust the lamp by means of a rod or link
(shown at S in Fig 6 and 16) attached to the lamp or its case or reflector, loosely;
and sliding upon the handle or holder The movement of this sliding rod, and also
of the two parts of the handle or holder in the other style of joint as in Figs 9 or
19 may be controlled by friction only, the two parts of the handle or holder being
connected by a link sleeve or equivalent device, or may be produced by a nut
screwing upon one and moving the other or by spring and rack, but we prefor a
combination of these shown in Fig 33 by elevation and two sections, in which the
two parts of a handle or holder H H (as of Figs 9 or 19) or representing the
handle or holder and a sliding piece respectively (as of Figs 6 or 16) may be slowly
and finely moved upon each other by revolving the nut n turning freely on H, but
engaging with screw thread on H' and a quick rough adjustment may be made by
pressing the two parts H H¹ together, and thus overcoming the spring V and so
releasing the threads on one from the nut upon the other, allowing free end wise
movement between them The above details of mounting and connecting lamps
as well as the arrangements and devices for cooling and protecting them herein-
after described are equally adapted for use with the ordinary forms of incandescent
lamps now employed In order to keep a lamp cool where desirable to do so we
extend its surface as much as possible wherever practicable and increase its capillary
attraction and retention of liquids, by roughening, corrugating or crinkling or
attaching to it by fusion cement or mechanical means, spun glass, silicate wool,
asbestos wire gauze as shown at W Figs 17 and 18, coils or brush like wires as in
Fig 19, or any fibrous, textile or porous material insoluble and sufficiently refractory,
preferably heat conducting and absorbent or a combination of them Also any or
all of the above may be applied to the reflectors, case, jacket, handle or holder,
or other accessories of the lamp. A finely perforated case or reflector is shown
in Figs 15 and 16 admitting and holding liquids in contact either with the
lamp itself or the inner wall of a jacket To facilitate cooling by simple con-
duction of heat from the glass thick metal of any kind may be brought
in good contact with a portion of the glass by electro deposition melting or other-
wise, and for this purpose we prefer mercury, as being also a good reflector and
readily applied Fig 27 shows in section a lamp jacketed with mercury m,
extending also into the handle H, which may be hollow, and further more divided to
provide for the circulation of the mercury. The mercury may also make electrical
contact at e and another insulated mass at c¹ Details of the construction of
mercury or other liquid jackets are shewn at Fig 28 where the lamp bulb is fused
or cemented into a portion of another of less curvature or larger diameter, or a
backing of any suitable material. Fig 29 shows 2 bulbs one blown within the
other and partially coalesced by fusion cement or contact Fig 30 shows a jacket
mechanically formed by a cell of any suitable material d and a ring g screwing into
it and enclosing the space m by forcing two packing rings ww on to the lamp
or only one ring may be used if the bulb is supported as at u in Fig 31
As non
amalgamating metals alone can be employed in conjunction with mercury, where
the use of platinum on account of cost weight or bad conductivity, or of iron or
steel is undesirable-we prefer to use aluminium or some of its high percentage

page_text: alloys. Or a lamp may be kept cool by the circulation of air or other gaseous
medium either between it and a casing as shown at Figs 20. 21. and 22 or within
a double case or jacket partially surrounding it, as in Figs 25 and 26, or by a
liquid cooling medium either in a double case or jacket as in Figs 25 or 26 or in
the case of a clear liquid like water in a case enclosing the lamp as in Figs 23
and 24. With any circulating cooling medium we make the interior surface of the
jacket or case irregular, with extensions &c as shown in Figs 20. 21 and 22 and
as also above described for the exterior surface of a lamp or case, and we also
provide the interior with ribs partitions and baffling plates for thorough circulation
as in Figs 25 and 26 and furthermore we fill the case, jacket or chamber where
suitable with subdivided material (preferably good heat conducting) as wire gauze,
coils, filings, shot and similar substances For the same purpose of cooling we
make all cases, jackets, fittings, handles or holders and other accessories to the
lamp of as thick and massive construction as the bulk and weight will permit,
metallic where possible and of great heat conducting power except where in some
special cases it is desirable that the exterior of the apparatus shall in parts be kept
much cooler than others, when we provide those particular portions with good non-
conducting shields of felt asbestos, char coal, porous clay or other suitable material.
Combinations of the above methods of cooling may be employed. When a clear
liquid cooling medium is used as shown by Fig 24 in a case d which must be closed
in front by a transparent plate t, that partition may be itself a lens a flat plate or
of a curvature that shall correct any undesired refraction caused by the liquid
when necessary to look through it, but usually is preferably of a shape that will
forin a converging liquid lens between itself and the lamp, as shown in Fig 24 For
using circulating cooling media we prefer to make the handle or holder of such
hollow or tubular construction that it may be readily attached to the fittings of
the lamp, either rigidly or by a pivotting or swivelling socket, and with freedom
of movement at the same time convey the cooling medium and maintain electrical
connection with the lamp. For a single socket arrangement and the use of a
gaseous cooling agent only, the handle or holder may as in Fig 20 consist of two
concentric tubular conductors k k¹ insulated from each other by any suitable
inaterial o either the inner, the outer or both tubes, fitting into a socket or con-
centric sockets in the case or jacket of the lamp d. The lamp electrodes e e¹ may
be connected electrically with the sockets of the case or jacket, or by and through
springs attached to the same, or directly (as shown in the figure) press upon the
inner and outer tube conductors respectively. Fig 21 is similar to the last
excepting to show that for the inner tube conductor of the other a solid central
conductor may be used if kept from contact with the outer, or a flexible insulated
wire conductor may be substituted If however, it is desired to convey the air
or other gaseous cooling medium away from as well as to the lamp the
central conductor must be hollow, or one of them may be partitioned by a
diaphragm into two parts Fig 22 is a side view (the handle or holder in
elevation, the case in section) of either Figs 20 or 21 conveying the gas which
escapes in front to the lamp only Fig 23 indicates the corresponding arrangement
for a liquid cooling medium handle or holder in which provision must be made for
reventing both conductors coming in contact with the liquid electrically, by
keeping one as an outer tube k and insulated solidly from the inner k', and, providing
that electrical contact is made by this outer one externally to the case or jacket
with one well insulated electrode of the lamp A third inner tube, not a part of
the electrical system, shown as h or a diaphragm partition may provide for the
circulation of the liquid. In all cases of solid and tubular or double tubular
concentric conducting handles, holders or supports, whether conveying cooling media
or not, we may provide them with sections or coupling sleeve joints fitting upon
each other as at C Figs 20 and 42 either straight, curved or bent, to alter the shape
of the conducting handle holder or socket. Another construction of handle or
holder of the other type of (style B) of pivoting, is shown in Figs. 25..and 26.in
which two separate hollow conductors kk (which may be of section shewn at H)

page_text: fit at b into two parallel side by side sockets in the case or jacket d The lamp
conductors c c¹ may terminate electrically in the sockets (if insulated from each
other) or may press directly or by and through suitable springs, upon the tubes
within the case or jacket, when any gas is used, but when employed for a liquid, a
separate conductor, insulated, must be brought up inside or outside one of the tubes
and terminate as a ring around it for contact with one of the insulated electrodes
The insulated wires connecting these tubular handles or holders of all kinds with
the source of electricity, may conveniently and appropriately be placed within a
flexible tube conveying the cooling medium. To obviate the destructive effect on
an incandescing filament or galvanic cautery of the strong current at first flowing
to it from certain batteries or generators, a switch or contact maker is so arranged
that as shown in Fig 35 where k and are the two conductors of a handle or
holder such as Figs 20 and 23 and O an insulator;-the sliding contact spring E
cannot be pushed forward to the position shown in the faint or dotted line for
connecting the two interrupted parts of together, without first connecting &
with at the point G and so short circuiting the battery or generator. By splitting
the forward end of the contact spring E as indicated, the current is not again
entirely broken before being put on to the lamp, which at first is connected up as
a shunt or derived circuit. Instead however of at once and abruptly breaking the
short circuiting contact at G and so opening the battery suddenly on the lamp,
means may be arranged to further graduate the current at first by either introducing
an increasing resistance between k and k¹ at G or taking out a resistance gradually
between the broken parts of k or elsewhere on the main circuit or both these means
in succession may be employed We prefer to use a resistance coil or rheostat upon
the handle or holder or it may be employed elsewhere in one of the following ways
As shown in Fig 34 at R. Q. a wire forming a loop of the circuit is wound, its two
parts side by side, as a double helix or two threaded screw on an insulated cylindrical
surface (preferably upon or into a temporarily softened insulating material) but in
any other usual way afterwards exposed flush as at M in section Then, a current
starting at Q for R will only get as far as E, the moveable sliding or screwing
contact piece and then back again to S, the length of the loop included by the
current depending on the position of E In this way the necessity of carrying a
terminal on E or maintaining a separate sliding contact with it is avoided A
similar arrangement may be effected very conveniently by the construction shown
at N where upon one conductor k a spiral groove is cut and into it is wound an
insulated wire, afterwards exposed and taken down flush with the grooved
conductor By this device the variable resistance wire is put in connection with
the conductor beneath, at any point where the contact piece E may be placed
In Fig 14 is shown a convenient form of simple switch or contact maker consisting
of a wedge or jamming block B upon a spring handle which removes it clear of the
terminals on each side of it when the contact is loose or imperfect
1
Having thus described the nature of the said invention and how the same
may be practically employed. What we claim and desire to secure by Letters
Patent is
1 An incandescent lamp, perforated, or otherwise formed to wholly or partly
enclose an open space or spaces substantially as and for the purposes set forth
2nd For incandescent lamps, a screen or reflector (with or without a lens)
perforated or otherwise adapted to hide the light from the eye when looking
through it substantially as described
3 An incandescent lamp, firmly hinged, swivelled or socketed upon its electrodes
and capable of being moved thereon, and its position thereby regulated in regard
to its holder or support substantially as described
>
4th The improved arrangement of parts as represented in Fig 33 for accurate
adjustment and regulation of the handles or holders of incandescent electric lamps
substantially as set forth
5th The herein before described methods or means of extending the surface of an

page_text: incandescent lamp or its accessories, or rendering it absorbent and retentive of
liquids or both substantially as and for the purposes specified
6th The combination of an incandescent electric lamp with a hollow jacket or
case containing mercury or other fusible alloy which will act both as a reflective
surface and as a cooling media substantially as set forth
7th For incandescent lamps, hollow or tubular electrical conductors which
convey also cooling media to the lamp or its accessories, as sot forth and
described
8th For incandescent lamps double concentric hollow or tubular conductors in
curved bent or straight jointed and sliding sections as and for the purposes set
forth
9th The combination with an electric lamp or galvanic cautery of a short circuiting
switch used with or without the resistance coil described as and for the purpose
set forth
10th The combination of an incandescent lamp with a cooling jacket or case
with or without reflectors, lenses or prisins substantially as set forth and
described
11th The combination of a flat incandescent lamp with a lens or prism attached
to or being part of the lamp and with or without a reflector, substantially as and
for the purposes set forth
12th An incandescent electric lamp formed with its neck or seal pushed or drawn
in toward the bulb substantially as and for the purposes set forth
13th A holder or support for incandescent lamps, provided with prongs adapted
to rest upon the bulb and with or without the addition of spiral springs (or with
or without spurs where the prongs complete the circuit) for further assisting in
maintaining electrical contact substantially as described
14th A holder or support for incandescent lamps provided with crossed loops
adapted to rest upon the bulb and with or without the addition of spiral springs
for further assisting in maintaining electrical contact all substantially as described
and shown in the accompanying drawings
15th In the manufacture of incandescent lamps moulding or forming the neck or
lower portion of the bulb so as to imbed therein solid bands or pieces adapted to
forin or hold the electrodes substantially as and for the purposes described
In Witness whereof we the said Otway Edward Woodhouse, Frederick
Lawrence Rawson, and Walter Harris Coffin have hereunto set our hands and
seals this sixteenth day of August in the year of Our Lord one thousand, eight
hundred and eighty three.