Abstract: Building constructions, building heating and/or cooling methods, and/or heating and/or cooling systems are provided that can include interior conduits configured to convey a fluid coupled with exterior conduits extending through the grounds surrounding the building.

Abstract: A hot-air type heater apparatus includes an air intake for receiving air from an area to be heated by the hot-air type heater apparatus. In particular, the air intake includes a suction fan for drawing air from a surrounding area into the hot-air type heater apparatus. The air from the surrounding area enters the hot-air type heater through the air intake. The hot-air type heater also includes an air passage to direct the air received from the air intake to a ceramic heater. The air passage allows the air received from the air intake to flow into the ceramic heater. The ceramic heater is then able to rapidly increase the air temperature. Furthermore, the hot-air type heater includes a warm air outlet coupled to the ceramic heater. The warm air outlet outputs the air heated by the ceramic heater into the area to be heated by the hot-air type heater apparatus.

Abstract: Structural wall panels and methods and systems for controlling the interior temperature of a building are provided. The structural wall panels advantageously include a fluid conduit disposed within an interior concrete layer of the structural wall panel where the conduit is adapted to convey a thermal transfer fluid through the interior concrete layer. A thermal insulation layer is provided between the first concrete layer and a second concrete layer, which can be disposed on an exterior surface of the wall. The thermal transfer fluid can be heated and/or cooled to regulate the temperature of the interior concrete layer and thereby control the temperature of the interior of the building. The first concrete layer can have a high thermal mass to increase the efficiency of the system.

Abstract: A cost-effective method of heating a space in a facility comprises: (a) determining a cost of electricity from an electricity vendor; (b) when the determined cost of electricity is below an electricity pricing setpoint, obtaining sufficient electricity from the vendor to heat a heatable material such as water above a first temperature setpoint; and (c) when the heatable material has a temperature above the first temperature setpoint and a space requires heating, heating the space using at least some of the heat stored in the heatable material. Such method is particularly cost-effective when using electricity charged at a time-of-use basis.

Abstract: A heater for a heating or heating and air conditioning unit employs a screen positioned between a heater and a fan of the unit. The screen disrupts air flowing from or to the heater to reduce noise generated by the unit when the heater is energized. The screen partially disrupts the air flow between the heater and the fan.

Abstract: The invention relates to a method of and apparatus for providing heat to a molten metal flowing through metal-conveying apparatus. The apparatus includes a molten metal-conveying channel, an enclosure for receiving and circulating combustion gases while preventing entry of the gases into said channel, a heat-conductive body of material separating at least part of the channel from the enclosure; and a combustion device for generating combustion gases and delivering the gases to the enclosure. Heat from the combustion gases is used to heat molten metal held in the channel, while preventing contact between the combustion gases and the molten metal. The body of material may be a trough used to form the channel, a tube for conveying the molten metal, or a tube acting as the enclosure, or the like.

Abstract: The invention relates to a building heating system which includes an insulated foundation (9) beneath the lowermost (12) of the building. According to the invention, the system comprises at least one heat pump (1, 2) that includes a heat absorbing side (2) located in the foundation space (9). The system also includes means (23) for distributing air from the foundation space (9) to spaces situated above the floor (12). The system also includes means (7) for delivering external air to the foundation space (9). The invention also relates to a method of heating a building.

Abstract: An improved fireplace heat exchanger apparatus having one or more generally first hollow members, wherein each first member has an internally disposed second hollow member thereby creating an annular space between the interior surface of the first hollow member and the exterior surface of the second hollow member. Ducting is provided to direct air/gas flow through the heat exchanger in a controlled, counter-flow manner. The interior portion of the second hollow member is configured to accept a flow of a heat transfer medium for transferring heat energy to a desired location while the annular space is configured to accept a flow of hot combustion gasses from the combustion chamber and direct it toward a chimney. A nozzle disc located in the annular passageway proximate the inlet of hot combustion gasses causes the gasses to circulate within the annular passageway to enhance heat transfer to the second hollow member.

Abstract: The present invention relates to portable heating systems for generating heat through various exothermic reactions excluding combustion of inflammable gases and liquids and carbon-containing fossil fuels. More particularly, the present invention relates to portable air heating systems generating heat by the exothermic chemical reactions and delivering heat to a target by conduction or convection. The present invention also relates to various portable heating systems supplying reactants, air, and/or heated air into and/out of such by a driving force generated by ordinary bodily movement of an user. Thus, the present invention relates to gloves, shoes, and cloths incorporated with the portable heating systems to keeping the user warm in cold weather. The present invention also relates to methods of generating heat by the portable heating systems and methods of applying such systems to the gloves, shoes, and cloths.

Abstract: A climate control system for a storage unit. The system includes a reverse cycle chiller; a fluid supply line in fluid communication with an outlet of the fluid side heat exchanger; a fluid return line in fluid communication with an inlet of the fluid side heat exchanger and the fluid supply line; at least one hydronic coil in optional fluid communication with the fluid supply line and the fluid return line, the at least one hydronic coil located in a room to be controlled; a controller in communication with the reverse cycle chiller and the at least one hydronic coil; an ambient temperature sensor in communication with the controller; an ambient humidity sensor in communication with the controller; a room temperature sensor in communication with the controller, the room temperature sensor positioned in the room; and a room humidity sensor in communication with the controller, the room humidity sensor positioned in the room. A method of controlling the climate in a storage unit is also described.

Abstract: Various embodiments of the present invention are directed to a high-thermal-mass hydronic furnace. In one embodiment of the present invention, a high-thermal-mass hydronic furnace includes a firebox, an insulated outer casing, a fluid-transport system, and a draft air-flow system. Fuel input to the firebox is combusted on a high-thermal-mass ceramic refractory. Heat from the fuel combustion is transferred to fluid within the fluid-transport system, via an internal heat exchanger, and circulated to a location external to the insulated outer casing for subsequent distribution to an interconnected heat-delivery system. The draft air-flow system regulates the fuel combustion by controlling the amount of air passing through the firebox.

Abstract: A heat controller for an object, having a composite material formed of a base material radiating a large amount of heat at a high-temperature phase and a phase-change substance having insulation properties at a high-temperature phase, having metallic properties at a low-temperature phase, radiating a small amount of heat at a low-temperature phase, and having a high reflectivity in the thermal infrared region at a low-temperature phase.

Abstract: A method for testing a heating system with at least one basic unit, which controls activating elements of individual heating circuits, with the basic unit being connected with setting units. To simplify the testing of such heating systems, the elements available in the heating system are arranged hierarchically in steps, with the steps being tested in a predetermined order, one after the other.

Abstract: A heat producing system for a building including a cylindrical housing having a closed upper end, a closed lower end, a cylindrical side wall therebetween, and a hollow interior. The closed upper end has an opening therethrough exposing the hollow interior. A piping system is disposed within the hollow interior of the cylindrical housing. The piping system includes a series of air inlets extending outwardly of the cylindrical housing adjacent to the closed lower end thereof. The piping system includes a single outlet pipe extending outwardly of the cylindrical housing adjacent to the closed upper end thereof. The single outlet pipe is coupled with a heating duct system of a building. A quantity of vegetable matter is positioned within the hollow interior of the cylindrical housing.

Abstract: In installations with water circuits such as domestic hot water or hydronic heating circuits a circulator pump is connected with a temperature sensor which energizes the pump as soon as the temperature of the water in the system falls below a predetermined temperature close to freezing.

Abstract: In a multi-unit installation system of fluid heating units such as hot water boilers, an outstandingly superior responsivity to load variations is obtained, and fluid of stable temperature is supplied by preventing useless starts and stops. In a units count control method, a plurality of fluid heating units (1) are arranged in parallel, these fluid heating units (1) and a load (2) are connected to each other through a fluid supply passage (3) and a fluid return passage (4), and the operated-units count out of the fluid heating units (1) is controlled in response to the load condition, wherein if a fluid supply temperature To in the fluid supply passage (3) is within a preset range, then a current operated-units count is maintained; if the supply temperature To is below the preset range, then the operated-units count is increased; and if the supply temperature To is above the preset range, then the operated-units count is decreased.

Abstract: A system for curing composite structures. A hollow bladder having opposing open ends is secured within a metal pressure vessel so as to define an annular space within the vessel surrounding the bladder. The open ends of the bladder are sealably attached to opposing entrances formed in the pressure vessel so that the bladder is sealed from communication with the vessel and is accessible through the opposing openings. An uncured composite part can be inserted into the bladder. Preheated and pressurized fluid is circulated through the annular space and thus around the bladder in order to cure the composite part. The composite part may also be encapsulated within a forming bladder member which is then removably inserted into the pressure bladder.

Abstract: A method for the automatic optimization of the heating curve of a heating controller in a heating plant is devised, whereat the heating curve is approximated by the potential function y=k.multidot.x.sup..alpha., in which function the coefficient k as well as the exponent .alpha. is evaluated in a simple manner. Furthermore, the influence of external energy may be taken into account.

Abstract: A method for controlling the condition of air in an enclosure, such as a greenhouse, containing growing plants involves reducing the heat load on the enclosure by reducing the rate of convective heat flow of air across the canopy of the plants. This is achieved by heating and dehumidifying the air in the greenhouse during periods of low light levels such as at night in a manner that minimizes ventilation for controlling humidity. Apparatus is also provided for controlling the condition of air in an enclosure using an air-brine-vapor direct contact heat exchanger. Regeneration of the brine from the heat exchanger can be achieved by heating the brine using heated air from the enclosure or hot flue gases such that latent heat and/or sensible heat contained in the air, gases, and/or vapor exiting the regenerator can be transferred to the sir in the enclosure.

Abstract: A method for purging water from flooded expansion tanks without necessitating the complete drainage and subsequent refilling of the systems allows for a stabilized hydronic water system in much less time with less effort and expense.

Abstract: The outer wall (19) of a heated room. In a variant, the air is heated by contact with the wall (19), which then is equipped with a Coanda effect air circulation (21). The air (24) is preheated before entering the room.

Abstract: An auxiliary burner provides supplemental thermal energy to a vehicle having a room and domestic water to be heated. The auxiliary burner operates efficiently at a rated thermal output when it is operated for at least the duration of a minimum operational cycle. A reservoir contains heat transfer liquid having a selected thermal energy storage capacity, measured by the amount of thermal energy required to heat the liquid from a minimum to a maximum operating temperature. The heat transfer liquid receives heat from the auxiliary burner. The thermal energy storage capacity is selected so that the auxiliary burner must operate at its rated thermal output for at least the duration of the minimum desired operational cycle to provide the selected thermal energy storage capacity to the reservoir.

Abstract: A heating system that reduces the cycling losses of a heat engine driven heat pump by storing rejected heat from the engine and using this rejected heat to meet a heating demand between periods of operation of the engine and heat pump so that over an extended time fewer start/stop cycles of the engine and heat pump are necessary. In a preferred embodiment a conventional storage-type hot water heater is used to store rejected heat, provide potable hot water, supply heat in the event of failure of the heat pump, supplement heat in periods of unusual demand, and provide low level heating requirements when heat pump operation would not be economical.

Abstract: A thermoelectric generating assembly for replacement of a heat exchanger mounted in a fuel-burning heater having electricity-consuming components includes a thermoelectric generator for supplying the electrical power requirements of the heater components and an adaptor portion for mounting the thermoelectric generator within the heater. The assembly possesses a size and shape which approximates that of the heat exchanger to be replaced and can be mounted within the heater in a manner like that in which the heat exchanger is mounted within the heater prior to removal. The method includes the steps involved in replacing the heat exchanger with the thermoelectric generating assembly.

Abstract: A water evaporating air conditioning, indirect heating and recuperative ventilation system comprising an air to air counter-flow heat exchanger having separate supply and return heat exchange chambers that are separated by a heat exchange membrane, water in air saturation elements and air movement means is provided. Air from the external environment is supplied through supply heat exchange chamber to enclosed space and air from enclosed space is moved through return heat exchange chamber and then expelled to the external environment. In air conditioning, water is evaporated inside the return heat exchange chamber and heat is conducted across heat exchange membrane from the air in supply heat exchange chamber to cool air supplied to enclosed space. In heating, heat is provided to air from enclosed space before that air enters return heat exchange chamber and air supplied to enclosed space is heated by heat conduction across heat exchange membrane and heating of the air in supply heat exchange chamber.

Abstract: A room which is substantially sealed or sealable from the surrounding atmosphere is conditioned by a plant which has a fluid heating or cooling unit, one or more heat exchangers, conduits which connect the unit with the heat exchanger(s), and a computer which is connected with sensors serving to transmit signals denoting the temperature t.sub.V of fluid in the conduit or conduits leading from the unit to the heat exchanger(s), the temperature t.sub.R of fluid in the conduit or conduits leading from the heat exchanger(s) to the unit, and the rate m of fluid flow in the conduit or conduits. These signals are used to calculate a so-called load range prevailing in the room in accordance with the equation (t.sub.V -t.sub.R).times.m. The calculated load range is compared with the load ranges of a pattern of load ranges which are characteristic of the plant, and the computer adjusts the unit or a mixing valve in the conduit or conduits leading to the heat exchangers(s) in order to change the value of t.sub.

Abstract: Apparatus for conditioning the air in an enclosure utilizes a primary direct contact air/brine heat exchanger in which enclosure air is contacted with brine from a reservoir for condensing water vapor in the enclosure air onto the brine to form dilute brine. A brine concentrator is provided in the form of a secondary direct contact air/brine heat exchanger in which segregated air, separate from enclosure air, is contacted with heated dilute brine from the reservoir for evaporating water from the heated dilute brine into the segregated air to form concentrated brine. The secondary heat exchanger operates to heat the brine while it is being contacted with the segregated air.

Abstract: Apparatus for humidity and temperature control of the air in an enclosure comprising brine-vapor-air direct heat exchanger apparatus disposed in communication with an enclosure and a brine reservoir arranged to store brine and to be exposed to naturally occuring temperature gradients for desired conditioning of the brine. The temperature gradients may be relatively short term, such as day-night or may be longer term, such as summer-winter.

Abstract: This invention relates to a method and apparatus for the extraction of the heat from the flue exhaust of a fuel burn in a furnace, stove or fireplace. The Heat Exchanger Flue can be adjusted vertically and horizonally in length to obtain a high efficiency in the extraction of the heat from said flue exhaust. The design is for the flue to have self cleaning features of soot and fly ash with storage and clean out areas, thus working well when coal is used for fuel. The heat can be extracted from said flue exhaust by air circulation or by water circulation. The design is flexable in the arrangements of the flue, thus allowing installation indoors or outdoors, or the combination of both.

Abstract: Method and device for operation of a heating plant comprised in a heating system which works with circulation of air. A partial flow (16) of the consumed air in the heating system is supplied to a heat exchanger (4) for heat exchange with intake air (12) coming from outside and with a return flow (14) of circulation air from the heating system. After passage through the heat exchanger (4) the mixture of intake air and return air is fed as heat delivering medium to the evaporator in a circulation heat pump (5). The quantity of air circulating through the heat pump is kept greater than the partial air flow which is exhausted from the heating system via the heat exchanger. With increasing demand for energy the partial flow is exhausted by means of a suction fan (7) and can, in addition, be mixed with the flue gases from a preferable water-carried heating boiler (2).

Abstract: A system for conditioning the air in an enclosure, such as a greenhouse, uses low grade heat contained in a liquid, e.g., condenser cooling water that is normally discharged downstream of a power plant. The system includes an indirect contact heat exchanger with a heat exchange surface having one side contacted by the fluid, and a direct contact air-brine heat exchanger associated with the enclosure including a blower for exchanging air between the enclosure and the air-brine heat exchanger. The system also includes a pump for exchanging brine between the direct contact heat exchanger and the other side of the heat exchange surface of said indirect contact heat exchanger. Thus, an efficient indirect, liquid-to-liquid heat exchange operation takes place between the brine and the low grade heated liquid; and an efficient direct, air-brine heat exchange operation takes place to heat the air in the enclosure without increasing its humidity.

Abstract: An air conditioner for an automobile, characterized by having an opening of a defrost duct for guiding air toward the inner face of a windshield formed in an upper portion of a heater unit, an opening of a foot duct for guiding air toward an automobile occupant's foot rest formed in a lower portion of said heater unit, a heater core incorporated in a central portion of said heater unit, a first mixing chamber formed in the proximity of said opening of said defrost duct and second mixing chamber formed in the proximity of said opening of said foot duct both within said heater unit, a first mix door for adjusting the amount of air flowing into said heater core and the amount of air bypassing said heater core and directly flowing into said first mixing chamber attached rotatably to the front side of an air inlet face of said heater core, a second mix door for adjusting the amount of air flowing through said core heater into said second mixing chamber and the amount of air bypassing said heater core and flowing d

Abstract: A method and apparatus to heat a forced-air supply utilizing hot waste gases in a flue. A flue closure housing is supported by a frame that is arranged to surround an opening in the chimney. The housing supports a heat exchanger having side walls formed of plates with a space between the plates being sealed by end walls to form a flow space for a forced-air supply. The heat exchanger is sealed to a flue closure plate forming part of the flue closure housing. The heat exchanger receives a supply of cold air from a motor-driven blower coupled to a header. Heated air from the heat exchanger is directed by a hot-air discharge header through an opening in the flue closure housing.

Abstract: An apparatus and process for frost control for the ambient air heat exchanger of a space conditioning apparatus. The ambient air heat exchanger is immersed in a fluidized bed enhancing the heat transfer and physically reducing frost formation. In a preferred embodiment, the fluidized bed is supported by a support bed of non-fluidized solid particles. In one of the embodiments the particulate beds may be desiccant materials. The space conditioning apparatus and method of frost control of this invention permits smaller ambient air heat exchangers and accommodates greater transient conditions due to the enhanced heat transfer and physical prevention of ice formation resulting from the fluidized bed.

Abstract: An air conditioning system of the air cycle heat pump type for selectively heating and cooling a residence or similar space environment. In one embodiment, a combustor and associated Brayton cycle turbine provide the primary drive to a compressor constituting the heat pump. In a second embodiment, the Brayton turbine is replaced by an electric motor coupled to drive the compressor shaft. An auxiliary turbine is also coupled to the drive shaft to provide auxiliary drive derived from the operation of a portion of the system at sub-atmospheric pressure. In this portion, during the cooling mode, water is evaporated into the system to further assist in cooling by removing the latent heat of vaporization.

Abstract: A heating system includes a water heating solid fuel stove operated in conjunction with a gas or oil fired hot water furnace. The two are connected in parallel and furnish heat to at least one heating zone and domestic hot water. In a first embodiment, a circulator pump is coupled to receive zone return fluid at its inlet and pump fluid from its outlet to the fluid fuel fired and solid fuel fired boilers. A first water valve is coupled between the circulator outlet and the solid fuel fired boiler, and a second water valve is coupled between the circulator inlet and the solid fuel fired boiler. In a second embodiment, separate circulator pumps are coupled in series with each of the fluid fuel fired and solid fuel fired boilers.

Abstract: The CO.sub.2 --CH.sub.4 reforming-methanation chemical cycle provides an ractive means of transporting energy, such as solar energy, from the place of generation to the place of use. CO.sub.2 /CH.sub.4 molar ratios of 2.0-7.0 permit the use of low-temperature pipelines, while lowering the carbon removal temperature of the system. Catalyst specificity is required to provide high methanation reaction temperature without carbon deposition.

Abstract: A heating system which uses bleed air to heat and recirculate cabin air for the passenger space of a vehicle.

Abstract: An energy-saving system for reclaiming the waste water contained in the ice shavings obtained from resurface ice at an ice skating rink, the system including a first tank for holding the ice shavings, a second tank for storing the waste water from the melted ice shavings, a first conduit system for conveying waste water from the melted shavings in the first tank to the second tank, a second conduit system for conveying waste water from the second tank to be sprayed on the shavings in the first tank, and a solar heating system for supplying heated waste water to the second tank.

Abstract: A method is disclosed for uniformly regulating and controlling the temperature in a multi-level building utilizing a common heat source. Only a single thermostat is required. The thermostat is placed in the room as near the end of the longest conduit and is set at the desired temperature. At least one and possibly a plurality of heating units such as radiators, each having its own output control valve, is placed on each level of the building. After the thermostat has been set at the desired temperature, each valve that controls the various heating unit is individually set. The radiator valve in the room in which the thermostat is located is opened all the way. The remaining valves are opened by a progressively smaller amount in those rooms further away from the thermostat. Once all of the rooms reach the desired temperature the valves are permanently set in order to prevent their unauthorized adjustment.

Abstract: The system described is useful in connection with a gas compressor that has a heat exchanger. Water conduits, a water pump and water control valve and cooler are connected in such a manner that the water circulated through the heat exchanger is directed to an energy consumption device wherein the heat is extracted to heat a room, office or the like. The control valve and cooler are arranged in the conduit so that the energy consumption device can be selectively bypassed by all or a portion of the water, depending on the heating demand.

Abstract: A compact heating and cooling system in which air ducts are connected to a host exchanger system through which a coolant fluid from a condensing unit or a heating fluid from a compact water heater is selectively directed by a control circuit so that the system may be mounted outside a building to be heated and/or cooled.

Abstract: The present invention relates to a heating and cooling system for structures such as residential dwellings. More particularly, the heating and cooling system includes one or more conduits disposed approximately six (6) feet underground and having opposite end extremities communicatively connected to the structure so as to define a closed air circulation system through the structure and one or more conduits. A fan assembly including appropriate controls is provided to induce and circulate air through the structure and through the one or more conduits such that a system of air may be continuously circulated from the structure through the underground disposed conduits and back through the structure.

Abstract: A method for constructing structures to minimize the amount of fuel necessary to heat the structure during winter months as disclosed. The structure of this invention maximizes the heat obtainable from the earth at depths substantially below the frostline by providing a basement having a relatively thin floor of conducting or noninsulating material and walls with a maximum of reasonable insulation both in the basement level and in the living-level first floor of the structure. Grids are provided adjacent walls and below windows and doors at the first floor level whereby cold air within the house will drop to the basement. The external walls are of standard construction with maximum insulation to protect against heat loss from within the structure. The basement floor adjacent the walls may be insulated if desired.

Abstract: A very well heat insulated water storage or accumulator tank of relatively large capacity as compared to the capacity of the hot water heating unit is interposed between the unit and the radiator system and is interconnected with the unit. Heated water from the top portion of the tank is used to preheat the unit prior to actuation thereof, and mixed water above a given temperature is fed to the unit from the tank during actuation, such that the corrosive condensation on the heating surfaces of the heating unit, caused by heating a cold surface, is eliminated thereby extending the useful life of the unit. When the unit is actuated, heated water from the unit fills the tank from the top side until a volume of non-heated return water from the radiator system, approximately equal to the capacity of the unit, remains in the bottom of the tank.

Abstract: An on-site system in which means for treating domestic sewage generated within a building located thereon are totally integrated with means for modifing space temperatures and for heating water for sanitary and other purposes therein to form a matrix of interrelated and interdependent functions acting together to deliver only non-polluting products to the environment and to achieve maximal energy conservation.

Abstract: A method for the chemical storage of radiant energy in which substituted naphthalenes undergo photochemical dimerization by exposure to radiant energy to form 1,2,2a,7,8,12b-hexahydro-1,8,2,7-ethanedihylidenedibenzo[a,e]cyclobuta[c]c yclooctenes, which on heating, revert to the original naphthalenes with the release of heat.

Abstract: A vehicle having an operators enclosure and an hydraulic circuit is provided with a heat exchanger to warm the enclosure. The heat exchanger is supplied with fluid from the return side of the hydraulic circuit thus eliminating the conventional engine coolant pipes.

Abstract: Disclosed is a heating unit consisting of a boiler chamber in which a two-phase liquid system is placed under a slight vacuum and supplied with a source of thermal energy. The activation of the source of thermal energy causes the lower phase liquid to vaporize and percolate through the upper phase liquid and circulate into a radiator section made up of finned tubes with an air flow being directed thereacross. The air flow absorbs the heat of the vapor which then is directed to the areas to be heated. The vapor continues to circulate into a header where the vapor is condensed back to the liquid state by a plurality of finned condensation tubes inside the header. The finned tubes of the radiator section have 90.degree. elbows extending upwardly into the header to prevent any condensed liquid from returning into the radiator of the system, and directing the vapor toward the coldest side of the header so as to enhance the condensation process.

Abstract: A system for the chemical storage of radiant energy in which either:A. 1,8-diaryl-1a,2,7,7a-tetrahydro-1,2,7-metheno-1H-cyclopropa[b]naphthalenes (1) are converted on heating to 1,2-diaryl-2a,8b-dihydrocyclobuta[a]naphthalenes (2) or 8,9-diaryl-benzocyclooctatetraenes (3), with the release of heat; and exposure of either compounds (3) or compounds (2) to suitable radiation results in the photochemical synthesis of compounds (1); orB. substituted naphthalenes undergo photochemical dimerization to form 1,2,2a,7,8,12b-hexahydro-1,8,2,7-ethanedihylidenedibenzo[a,e]cyclobuta[c]c yclooctenes. On heating, the latter revert to the original naphthalenes with the release of heat.