Abstract: An inflatable hand-held snorkeling float supports a see-through underwater viewing module having a top glass and a bottom glass joined by a collapsible sidewall. A pneumatic chamber surrounds the viewing module. The chamber has a top deck and a bottom deck symmetrically pitched about a central longitudinal axis to form a wedge-shape having an included angle between about 5° and 15°. The top and bottom glasses are also wedge-shaped symmetrically about the longitudinal axis. Handles extend from the sides of the chamber, and are generally centered along a central transverse axis. An optional accessory mount may be affixed to one of the decks adjacent the bow. The accessory mount can be configured with a pair of dedicated connection pads to hold a dive flag and a camera, or two cameras, etc. The configuration of the float provides flotation symmetry when roll-inverted but flotation asymmetry when pitch-inverted.

Abstract: A ship handling device including a joystick lever configured to be inclined in a desired direction at a desired angle, and a ship handling control device configured to control driving of a forward-backward propeller generating a thrust in a front-and-rear direction of a ship body and a thruster generating a thrust in a left-and-right direction of the ship body. The ship handling control device has a normal mode in which driving of the forward-backward propeller and the thruster is controlled according to an input signal from the joystick lever, and a thruster single-driven mode in which driving of only the thruster is controlled according to an input signal from the joystick lever, and the ship handling control device is connected to a mode changing switch with which a switchover between the normal mode and the thruster single-driven mode is performed.

Abstract: Method and apparatus for an improved recreational canopy which may be used with watercraft wherein the canopy is constructed by using a pair of flexible, resilient rod-like members wherein one end of each of the flexible rods is inserted through mating apertures in an upright support member mounted onto the watercraft, or other structure, so that the rods are bowed outwardly and frictionally held in the stanchion. A canopy, which may incorporate solar cell fabric, is attached between the rods so that the canopy generally appears to be in an elongated V-shaped structure which stretches across a portion of the supporting structure, such as a watercraft, between the flexible rods. The upper end of the upright support member may be pivotable and the rod-like members may be disposed in a cap removably disposed on the upper end of the upright support member. A lighting system including an alternative power source being provided on the canopy.

Abstract: Use: in building of light, predominantly individual sports and tourist floating craft. Essence of the invention: the display on the surface of the swimming board or surfboard broadcasts the information received both from video cameras located either on the surface of the floating craft or on the supports or pulled in tow under the water, and from external mobile and other devices. The display is configured to stabilize the displayed image and compensate effects caused by water refraction coefficient, and has the ability of creating animated graphic marks and tips to facilitate user's balancing on the floating craft.

Abstract: A water window apparatus including a main water window element, and a plurality of retaining flanges, along with interlocking teeth that fixedly communicate with one another to fixedly retain the main water window there between. The main water window is hollow, as well as monolithic and hermetically sealed to maintain its integral buoyancy, and further has a top that includes a magnifying element that imparts magnification when viewed therethrough.

Abstract: A floating construction comprising a container filled fully or partially with water, the lower portion of the container being located within a surrounding body of water and the water surface level of the surrounding body of water being substantially lower than the water surface level inside the container, the container comprising transparent walls or walls with transparent sections and at least one open opening for entering the container, which at least one open opening is located below the surface level of the surrounding body of water, and which floating construction comprises space for spectators observing activities taking place inside the container, wherein the floating construction comprises at least one ballast tank, which ballast tank is connected to the container with a controllable pressure connection, and which ballast tank has controllable water connection to the surrounding body of water.

Abstract: Various aspects of a watercraft with a controllable imaging device are disclosed herein. The watercraft includes a rotatable housing provided in a recess located underneath the watercraft. The recess further includes a roller assembly to movably engage the rotatable housing within the recess. An imaging device is positioned within the rotatable housing. One or more control commands are received by the imaging device from an electronic device to enable capture of one or more images.

Abstract: Assemblies and methods are provided to allow a temporary alternate door (e.g., an observation door for use during search and rescue (SAR) missions) may be placed in a fuselage opening normally closed by a dedicated personnel door. The assembly may be provided with a central support pole attachable to interior structure of the aircraft fuselage so as to be disposed in an upright position within an interior of the aircraft fuselage (e.g., within the aircraft's cargo hold), and at least one stand-by alternate door (e.g., an observation door) which is sized and configured to be operatively accepted by the aircraft fuselage door opening when the dedicated primary aircraft door is in an opened and stowed condition. Typically a pair of stand-by alternate doors are removably connected to the central support pole so as to be capable of being movably deployed into a position to close the aircraft fuselage opening when disconnected from the central support pole.

Abstract: A floating construction (1, 11) includes a vessel (2, 12) partially or fully filled with water and with transparent walls or with walls including transparent sections, and space (3, 5, 6) provided around or partially around the vessel, where the vessel includes at least one opening allowing the surrounding water to enter into the vessel, wherein the space (3, 5, 6) provided around the vessel (2, 12) is enclosed to provide interior observation area for activities taking place inside the vessel.

Abstract: A system that incorporates teachings of the subject disclosure may include, for example, a water vehicle including a deck that accommodates a group of passengers above a waterline and an observation gondola accommodating the group of passengers below the waterline. The access between the observation gondola and the deck is provided by way of an aperture in a top of the observation gondola. The observation gondola includes a transparent floor and walls allowing the group of passengers to enjoy an underwater experience without exposure to the water and while maintaining an unobstructed panoramic view of the underwater environment. The underwater observation gondola can include a substantially open top, which may include a sun screen or weather protective cover. The open top exposes the observation gondola to fresh air, while alleviating any claustrophobic sensations as might otherwise be experienced by passengers during underwater observation. Other embodiments are disclosed.

Abstract: The present invention refers to a stand-up board (1) endowed with a lighting system and an underwater viewing window (3) hermetically placed between the upper (2) and lower (8) plates, provided with a waterproof box for feeding battery (6), and a vapor purge valve (7); furthermore, the referred board has a visual alert signaling system (4 and 5) arranged along bow and stern of the respective stand-up board (1), that may be self-powered or use a feeding battery.

Abstract: Described are submersible assemblies including a support structure comprising a pair of flotation devices and a cabin pivotally coupled to the support structure between the pair of flotation devices having an outer enclosure encapsulating an inner cabin, wherein the cabin is configured to rotate between a raised position above a surface of a body of water and a submerged position, wherein at least a portion of the cabin is below the surface of the body of water, and wherein the inner cabin is configured to maintain substantially the same attitude as the support structure when the cabin rotates between the raised position and the submerged position.

Abstract: A system that incorporates teachings of the subject disclosure may include, for example, a water vehicle including a deck that accommodates a group of passengers above a waterline and an observation gondola accommodating the group of passengers below the waterline. The access between the observation gondola and the deck is provided by way of an aperture in a top of the observation gondola. The observation gondola includes a transparent floor and walls allowing the group of passengers to enjoy an underwater experience without exposure to the water and while maintaining an unobstructed panoramic view of the underwater environment. The underwater observation gondola can include a substantially open top, which may include a sun screen or weather protective cover. The open top exposes the observation gondola to fresh air, while alleviating any claustrophobic sensations as might otherwise be experienced by passengers during underwater observation. Other embodiments are disclosed.

Abstract: A system that incorporates teachings of the subject disclosure may include, for example, a water vehicle including a deck that accommodates a group of passengers above a waterline and an observation gondola accommodating the group of passengers below the waterline. The access between the observation gondola and the deck is provided by way of an aperture in a top of the observation gondola. The observation gondola includes a transparent floor and walls allowing the group of passengers to enjoy an underwater experience without exposure to the water and while maintaining an unobstructed panoramic view of the underwater environment. The underwater observation gondola can include a substantially open top, which may include a sun screen or weather protective cover. The open top exposes the observation gondola to fresh air, while alleviating any claustrophobic sensations as might otherwise be experienced by passengers during underwater observation. Other embodiments are disclosed.

Abstract: An underwater viewing unit includes a tube insertable into a through-hole of an air mattress, a rest for the viewer's head provided at the lower end of the tube, and a transparent panedisposed within the tube. The head rest is formed by an inflatable beaded body connected to the upper rim of the tube and extending over less than 360° to leave free a peripheral region outside the tube for free breathing.

Abstract: A transparent and shark-repelling surfboard or flotation board made of transparent super microcellular polymer foam with transparent coating. The surfboard or the flotation board has a locater device for locating large aquatic animals, and an alarm device for alerting a rider of large aquatic animals, such as sharks, located by the locater device. The surfboard or the flotation board also comprises a repellent or deterrent signal generator that is configured for transmitting interference signals to disrupt the electro-sensory perception system of the aquatic animals.

Abstract: Disclosed is a window housing for use in combination with a transducer style thru-hull fitting. The window housing is sealingly attached to the thru-hull fitting by use of a first securement cap. The window housing having a window panel positioned adjacent to the outer side surface of the vessel hull. A tubular shaped light assembly preferably housing LED's may be inserted into the window housing and secured thereto by the use of a second securement cap. Alternatively a tubular shaped camera assembly may be inserted into the window housing and secured thereto by the use of a second securement cap.

Abstract: The present invention is a view port suitable for installation under the water line of a vessel wherein the view port comprises a flange made from a corrosion resistant material and a body made from a heat resistant material. An alternative embodiment of the invention is an underwater light in which a high intensity discharge light is installed into the above mentioned view port. The light may be swiveled while installed in the view port in order to direct the light along a desired path.

Abstract: An improved watercraft having a viewing system, and a kit for installing a viewing system in an existing watercraft. The watercraft includes a viewing opening through a portion of the bottom of the hull and a viewing system is attached thereto. The viewing system includes a substantially transparent viewing window that is disposed within the viewing opening, an attachment that attaches the viewing window to the bottom of the hull and a seal that creates a watertight seal between the viewing window and the bottom of the hull. The kit includes the components of the viewing system and a template for marking the hull of the watercraft.

Abstract: The invention concerns the structure of a “SUBMERGED UNDERWATER OBSERVATION BOOTH”, including a floating station on water surface, and a piping system to convey fresh air and power into the SUBMERGED BOOTH. The SUBMERGED BOOTH provides an atmospheric environment with all the necessary equipment and facilities to a person doing underwater observation or research. The SUBMERGED BOOTH can travel underwater in both vertical and horizontal directions. The SUBMERGED BOOTH is designed either in the shape of a cylinder with two half-spheres at both ends, or in the shape of a sphere, with clear plastic wall all around, to provide the observer with maximum viewing angle. The invention aims to provide a system for a wide application area and many purposes of use under water such as: exploration, tourist, research, maintenance, repair, etc. . . .

Abstract: A personal water craft is a device having a unitary hull body that includes a substantially horizontal planar deck for supporting an occupant in a pronate position and a shell integral with the deck, wherein the shell is submersible into water. A cushioned pad is affixed adjacent to the deck, thereby providing a comfortable resting position for the occupant. A transparent viewing panel is affixed to the bow end of the hull, thereby forming a window for the occupant to look through. A joystick for controlling the direction of said personal water craft is also included, wherein the joystick is electrically coupled with a battery, a motor and a propeller.

Abstract: The invention relates to a floating body, especially a floating body used as a support for an underwater tunnel (11). In order to obtain a high degree of freedom and a large amount of stability while at the same time guaranteeing easy assembly, a frame structure (49) is provided in the form of a horizontal grating, wherein floats, ballast bodies, dam chambers or similar useful hollow bodies (50) are fixed in the rectangular, especially quadratic free areas of said grating as tanks.

Abstract: The invention relates to a floating body, especially a floating body used as a support for an underwater tunnel (11). In order to obtain a high degree of freedom and a large amount of stability while at the same time guaranteeing easy assembly, a frame structure (49) is provided in the form of a horizontal grating, wherein floats, ballast bodies, dam chambers or similar useful hollow bodies (50) are fixed in the rectangular, especially quadratic free areas of said grating as tanks.

Abstract: A mobile undersea habitat includes an elongated vessel having a hull providing an elongated recess opening downwardly to the sea, and a cooperatively dimensioned elongated column seated within the recess. The column includes an elongated structural member with a conduit extending along its length and an elongated panel providing a closure for the hull opening which also functions as a support member in the column. A support member pivotally mounts one end of the support member in the hull, and a pivot pivotally mounts one end of the structural member in the hull at a point spaced from the support member pivot. A habitat is provided at the other end of the column and it is pivotally mounted to the structural and support member so that it maintains a horizontal attitude at any angular portion of the column. The conduit provides a passage from the vessel to the habitat in which a transport capsule carries personnel and supplies.

Abstract: A personal swim craft that has a liquid filled viewing area that is simply and inexpensively created within the craft requiring no tooling for molds or related costs. A walled cavity through the craft is sealed at its upper and lower openings with transparent panes. These panes are sealed in place without drilling or tapping holes or otherwise altering the surface area of the panes. The void between the transparent panes is filled with a transparent liquid via a vent that can be within the upper transparent pane or integrated into the craft adjacent to the upper pane and extending through the craft into the cavity void. The upper pane of the viewing area is slanted aft to allow extraneous water to run off into scuppers or vertical vents adjacent to the aft perimeter edge of the upper pane. These vertical vents and a forward set of vertical vents also remove air bubbles that may become trapped below the outer surface of the lower transparent pane.

Abstract: The invention relates to a discovery boat (1) with a viewing cabin located beneath the surface of the water. Said viewing cabin has large viewing windows looking out to the side and forwards. According to the invention, the viewing cabin is a transparent vessel which is open from above and which is located in an opening of a deck, said deck extending between two floating bodies (2). This ensures a simple, versatile construction.

Abstract: An underwater observation device in combination with a buoyant craft provides an observer with a clear and unobstructed view of underwater scenes. The underwater observation device comprises an upper transparent window, a lower transparent window, and a body portion disposed between the upper transparent window and the lower transparent window. The body portion has a centrally disposed cavity that is filled with a transparent fluid material and a vent for permitting the ingress and egress of the transparent fluid. A person lying in a prone position on a buoyant craft can comfortably peer down into the water and enjoy the underwater scenery. The underwater observation device of the present invention has an innovative design that eliminates visual obstructions such as air bubbles, debris, and condensation.

Abstract: A device to observe the sea bed from the deck of a vessel is formed by a cubicle that has attachment points to attach it to the structure of the stern of the vessel. This cubicle has a vertical wall that forms a sealed block on the bottom wall of which are the lighting points to illuminate the sea bed. The base of the rest of the cubicle has a resistant transparent glass in contact with the water, since the lights and this glass are on the same plane and below the water line of the vessel. The device has an inclined mirror in the upper part and forms a prolongation of the inclined surface of the block, in which mirror is reflected the sea bed which is seen through the glass and at the same time may be observed from any part of the deck of the vessel.

Abstract: The present invention is characterized by an underwater sightseeing craft, wherein a plurality of displacement bodies for sightseeing equipped with underwater sightseeing rooms are provided and paralleled with a fixed distance therebetween, wherein floating cavity bodies are provided outside each of said displacement bodies, wherein whole the said bodies are combined and integrated into one body by means of connecting members so as to be in a symmetrical form, wherein sightseeing windows are formed on each of said displacement bodies for sightseeing at a fixed depth below water, and wherein said floating cavity bodies are located so as not to obstruct a view through the sightseeing windows.

Abstract: An underwater viewing device for use during ice fishing for permitting a user to see underwater through a hole in the ice. The device includes a viewing tube having open top and bottom ends. An annular resting flange is disposed around the viewing tube. An elastomeric O-ring is disposed around the viewing tube. The O-ring has a diameter sized such that the O-ring is held in tension on the viewing tube. The O-ring is positioned on the viewing tube between the top end of the viewing tube and the resting flange with the O-ring resting on the viewing tube such that the viewing flange is held in a relative position with respect to the resting flange.

Abstract: An air-to-water surface operating underwater viewing craft which succeeds in providing man with both speed and the same extravagant vision for underwater viewing that he/she possesses above the water with respect to field of view and clarity. This is achieved through proper implementation of a number of factors which are all locked in a perpetual relationship one to the other. The desired results are obtained by employment of a viewing window which is laterally curved around the sides of a prone viewers' face and which extends foreward and backwards sufficiently to exceed mans' field of vision threshold in all directions. The viewers' head is supported by a headrest which provides a viewing reference point for the viewers' eyes. Around this arrangement is built a flotational device which features two stabilizing pontoons positioned on starboard and port sides providing correct craft posture and predetermined draw. A two axis joystick controls two retracting electric thrusters providing full maneuverability.

Abstract: Watercraft has a hull with a viewing opening therein extending between upper and lower portions of the hull. A transparent viewing unit is fitted within the viewing opening and has a periphery spaced apart from side wall of the viewing opening to define a draining space between the side wall and the viewing unit. This provides a peripheral clearance extending generally around the unit for draining water through the hull irrespective of angle of the watercraft with respect to the horizontal. A cowl extends peripherally around the viewing opening and has a lower portion sealing the viewing opening to prevent passage of water, and an upper portion to embrace portions of a person's face to exclude extraneous light.

Abstract: A buoyant board for viewing underwater objects while an observer is lying in a prone position is of seamless, unitary construction, and has a viewing well extending through the body of the board that is integrally formed with the body. The body may be formed of rotomolded plastic. The board may have a vent to relieve excessive air pressure within the board, but is otherwise sealed so as to be substantially watertight. The board may also have a drain plug or valve that allows water that accumulates in the interior of the board as a result of condensation or leakage to be expelled. The upper end of the viewing well has a contoured shape that conforms generally to the contours of the human face. A transparent window is mounted at the lower end of the viewing well and may be recessed from the bottom of the board or mounted flush with the bottom of the board by providing a countersunk edge around the periphery of the lower end of the well.

Abstract: A recreational boat with a viewing plane which may be in contact with the water when the boat is ladened. The boat being constructed from two main pieces, a transparent hull piece formed with sponsons specially shaped to assist in maneuvering and a deck piece mated with the hull. The peripheral edges where the two major pieces are mated forms a splash guard and may be protected with a bumper. The deck is fabricated with seats, steering column, motor mount and storage compartment access doors. A second viewing plane may be formed in the bow of the hull and accessories such as a hand rail may be mounted on the deck.

Abstract: In a semi-submersible ship, magnifying panoramic view windows are provided that are watertight, strong, highly durable, and resistant to impact and optical occlusion. A laminated transparent sheet is formed that is surrounded by a ribbed gasket. A steel frame provides uniform compression on the gasket and prevents it from extruding away from the transparent sheet. Bolts are used to attach the transparent sheet to the hull of the ship.

Abstract: A hydro-propelled ship is provided which consists of a hull having a double wall, so as to float on a top surface of a body of water. A pair of propulsion turbines are each affixed to a starboard side and a port side of the hull of the ship in a catamaran configuration below the top surface of the body of water. A mechanism is carried within the hull of the ship for generating power to operate each of the propulsion turbines to produce a water jet to propel the ship along the body of water. A pair of adjustable rudders extend downwardly into the body of water from the stern of the hull for steering the ship.

Abstract: An underwater vehicle is disclosed being equipped with a passive optical observation system. The underwater vehicle has an observation window at its disposal which exhibits a diameter in the range from 0.3 to 3.0 m and a curved surface. In order to increase the sensitivity of the passive optical observation system and the ability to detect distant objects, the observation window is part of the passive optical observation system. The entrance pupil of the observation system exhibits a diameter in excess of 0.1 m.

Abstract: A water craft which comprises a motor propelled floating portion which has two spaced-apart hulls which are connected by an elevated bridge. The water craft further comprises a submersible cabin which is arranged to be raised and lowered with respect to the floating portion of the craft, the cabin providing accommodation for underwater observers. The cabin is connected to each hull by fore and aft pivotable arms and is movable between a first position above the waterline of the floating portion of the craft to a second, submerged, position. The cabin is accessed from the floating portion of the craft when the cabin is in the first position and, in order to provide for fail-safe operation, the cabin is ballasted for positive buoyancy when it is submerged. The cabin incorporates a tower which is dimensioned to project above the waterline at all times, including when the cabin is sumberged to the maximum extent permitted by the pivotable arms.

Abstract: A semi-submerged water vehicle having a small rider's compartment designed to accommodate primarily a single rider that can operate the watercraft in either a standing or a seated position. There is provided both an underwater porthole and an above-the-water porthole both of which can be looked through by the operator when seated within the passenger compartment so as to afford both above-the-water and under-the-water viewing to the rider.

Abstract: An improvement is made in terms of rolling of a semi-submerged glass boat whose hull is formed of the main hull and float tanks provided on the lateral sides of the upper part of the main hull, and anti-rolling fins each projecting outside of a straight line connecting the outer end part of the bottom of the float tank and the outer end part of the bottom of the main hull are provided on the opposite sides of the main hull respectively.

Abstract: A "glass boat" is provided including wooden structural members provided with a skin of plastic. The plastic panels are secured to mahogany structural members with stainless steel screws. An outer mahogany strip is applied on top of the screws thereby placing all the edges of the panels between inner and outer mahogany portions. The boat is further provided with foam filled seat compartments to permit the boat to float even when capsized.

Abstract: The appliance for assisting a swimmer in swimming, floating and being towed by a boat, includes a substantially board-shaped floating body having a leading edge and a trailing edge each of which have a V-shaped cross section. The floating body has a glass panel with a transverse reinforcing web mounted centrally therein so that the swimmer can observe through the floating body. The floating body has two longitudinal sides each having a handle in the shape of an arcuate protrusion projecting therefrom. Each of the handles is located in the middle of its longitudinal side, and the longitudinal sides are divided by a central transverse axis, each of the handles having a through-going handle opening positioned between the transverse axis and the leading edge. Fastening means, such as screws, are provided on each handle and a tow rope is attached to each of the fastening means by one of its two ends.

Abstract: A swimming aid comprises a floating body and a bottom viewer and may be used at a swimming pool or in the sea. The floating body is U-shaped in cross section and has a hood at the top thereof. The floating portion buoyantly supports the upper half of the swimmer's body in the water. The bottom viewer is made of a transparent material such as vinyl chloride resin and takes the form of a dome. The bottom viewer is installed on the top of the hood and provides a wide forward or underwater view of the swimmer. The swimmer when laying with his body on the bottom of the floating body can swim without great resistance while looking forward or downwardly underwater through the bottom viewer.

Abstract: A submersible observation vessel having a transparent acrylic hull. The hull comprises a plurality of transparent acrylic cylinders, a plurality of seals to prevent leakage between the cylinders of the hull, a front hatch hinged on the first seal, and a bulk head having an aft hatch welded to the last seal. An integral cradle supports the vessel when on dry dock and provides a medium for lifting the vessel into and out of the water.

Abstract: An apparatus for underwater surveillance that consists of a floating platform having bow and stern with an aerodynamically true forward cowl formed on the bow end, the forward approximately one-third of the platform. Immediately aft of the cowl there is disposed a viewing assembly placed in a clearance formed centrally through the platform, and the viewing assembly is a tightly sealed transparent member having top panel, bottom panel and side panel and defining a volume that is maintained liquid free thereby to enable maximum viewing efficiency at all times.

Abstract: The invention relates to an underwater viewing device wherein a viewer can immerse the lower portion thereof into a body of water and view clear, undistorted images of objects which appear immediately below the underwater viewing device. The underwater viewing device is provided with a viewing tube having a plurality of opaque sides that project upwardly from a horizontal planar surface made of clear plexiglass. The opaque sides rise upwardly at a forty-five degree angle relative to the horizontal planar surface. This viewing tube is open at the uppermost end and permits viewers to look therein without the requirement of placing their head into contact with the viewing tube. Additionally, the viewing tube is not required to be covered as in prior art devices. The basic concept of the underwater viewing device is embodied in a hand held unit while there are also disclosed other applications such as air mattresses, inflatable boats and catamaran-type paddle-wheel boats.

Abstract: An aquatic show boat has a pair of separated, long narrow hulls joined in a parallel fashion (catamaran like) by a plurality of connecting pieces which together with both hulls enclose the perimeter of at least one activity area. Demonstrations, exhibits and recreation, etc. in an activity area can be viewed from observation decks provided on the hulls, or on the hulls and connecting pieces.

Abstract: An underwater window for vessels which is provided to cover an opening made on the hull has a first transparent plate curved to form a convex surface bulging toward the outside of hull outwardly from the hull. One or two additional transparent plates are provided to cover the concave space which is formed on the cabin side by the first curved plate. The space formed by the curved plate and the additional plate, or plates, is filled with a liquid. The liquid contains distilled water and an algaecide, such as CuSO.sub.4 and has its pH adjusted to with the range of 7.0-7.6.

Abstract: In accordance with the present invention a viewing device for flotation bodies is provided which comprises a body having an interior defined by its side walls and at least one transparent end wall. In one embodiment using two transparent end walls, the transparent end walls define spaced-apart viewing ports, one port being normally above the surface of the water and the opposite port being below the surface of the water. The interior of the body is adapted to be substantially condensation free by evacuating the interior of the body and sealing the body in the evacuated condition or, more preferably, filling the body with a fluid to the exclusion of air so that condensation and air bubbles are thereby avoided. In a preferred embodiment the viewing device consists of a single piece body having a single transparent end wall.

Abstract: A frame made up of structural pieces (wooden) and hardware pieces interconnecting them, and a flexible hull. The frame includes a main frame and coaming. The main frame is separable transversely at the middle, and each half thus formed is insertable into one end of the hull which is drawn taut over the frame half, after which the coaming is applied to the main frame and the hull secured thereto. The frame is made up of a plurality of relatively short pieces that are separable or foldable to enable them to be put in correspondingly short bundles, for carrying purposes.