Abstract: A game scent delivery system includes a plurality of projectiles having a game scent and a projector that is capable of projecting one of the projectiles to a desired location. The projector includes a projectile launching member, a projectile storage unit that has a sufficient size to store a predetermined number of the projectiles, and a single projectile dispensing unit. The single projectile dispensing unit is integral with the projectile storage unit and is capable of dispensing a single projectile of the plurality of projectiles to the projectile launching member while retaining all of the plurality of projectiles in the projectile storage unit, except for the single projectile.

Abstract: A showerhead according to the present invention includes a housing, a baffle located within the housing, a fluid-permeable absorbent element, and a fluid distribution element. The baffle and the upper lid of the housing define a fluid chamber that receives fluid from a fluid inlet. The fluid flows through seep holes in the baffle and into a second fluid chamber that contains the absorbent element. The fluid distribution element encloses the absorbent element within the second fluid chamber. The fluid distribution element includes a plurality of holes and a plurality of protrusions configured to release fluid from the second fluid chamber.

Abstract: A showerhead according to the present invention includes a housing, a baffle located within the housing, a fluid-permeable absorbent element, and a fluid distribution element. The baffle and the upper lid of the housing define a fluid chamber that receives fluid from a fluid inlet. The fluid flows through seep holes in the baffle and into a second fluid chamber that contains the absorbent element. The fluid distribution element encloses the absorbent element within the second fluid chamber. The fluid distribution element includes a plurality of holes and a plurality of protrusions configured to release fluid from the second fluid chamber.

Abstract: A scent dispersion apparatus for delivery via an arrow shot by a bow. The apparatus uses an arrow tip using a compression fitting for attaching to the arrow shaft. A scent dispersion head slidably fits over the arrow tip, and contains a sponge which holds liquid scent. The arrow tip acts like a plunger to force the scent liquid out upon target impact. The arrow tip includes O-rings to hold the dispersion head in place until target impact.

Abstract: There is described, in conjunction with a vibrating orifice plate type atomizing dispenser, a refill reservoir which has a wick mounted in a unitary wickholder to provide precise locating of the wick in relation to the vibrating orifice plate in the dispenser. There are also described a novel reservoir overcap and wickholder construction in which mating tubular surfaces on these elements telescope together to ensure a good liquid seal without interfering with the wick. There is also described a novel camming arrangement which enables the overcap to be removed easily from the reservoir.

Abstract: A liquid is held in a high viscosity solids suspension in a reservoir and is separated from the suspension by a capillary element which transfers the liquid to a vibrating orifice plate from which the liquid is ejected in the form of aerosolized liquid droplets.

Abstract: A fluid collection and distribution system (irrigator) configured from a flexible or semi-flexible material which can conform to various sizes and shapes of terrain. According to various embodiments of the irrigator, seep holes may be provided. Additionally, the irrigator may be configured from a porous material. In various embodiments, the irrigator contains through holes for various plant life to take root through and for facilitating drainage. The irrigator may have multiple, distinct passages for the collection and/or distribution of multiple fluids and or gases. In addition, a irrigator forming device is provided for forming the irrigator. Still further, an irrigator cutting device is provided for customizing and repairing the irrigator.

Abstract: Liquid dispensing apparatus comprises a tubular casing having at one other end an inlet nozzle connectable to a source of gas under pressure and at its end an outlet nozzle having an orifice in communication with an expansion chamber bounded by sides which diverge away from or converge towards the orifice. The liquid dispensing apparatus containing a pen-like liquid source having an absorbent nib at least partially within the casing with the nib within or in close proximity to the nozzle orifice. The pen-like source may comprise a felt-tipped pen.

Abstract: Disclosed is an irrigation assembly that comprises a soaker hose having a liquid permitting region and a liquid barrier, which preferably is a tube that is disposed concentrically about a portion of said liquid permitting region and is axially movable relative thereto. The tube is water-impermeable such that water flowing through the soaker hose is not permitted to exit the hose along the axial region of the liquid permitting portion that is covered by the tube.

Abstract: A seeping irrigation system has one or more tubes or conduits, and one or more strings or threads. Each string or thread connects the tube(s) or conduit(s) by passing through the wall of tubes or conduits. At inside of tubes or conduits, the inside parts of strings or threads touch with fluid, then the fluid is seeped out through strings or threads. The parts of strings or threads at outside touch a plant material such as soil etc., so that the seeped out fluid goes into the plant material such as soil for plants use. One end of tubes or conduits has been stopped, and the second end of the tubes or conduits connects to the source of fluid.

Abstract: An arrow (10) intended for dispersing olfactant (for example, for use in deer hunting) and comprising an elongate body (12) having an internal cavity (14), this cavity (14) having a container portion (18) to accommodate a frangible liquid container (20). A container rupturing device (24) is disposed within the cavity (14) adjacent the container portion (18), this device (24) being such that the arrow, with a container (20) on board, can be launched from a bow without rupturing the container (20), but that upon the arrow (10) striking a target, the device (24) will rupture the container. A wick (40) is disposed within the cavity (14) adjacent the container portion (18), this wick (40) being capable of absorbing the liquid released from the rupture of the container (20). The body (12) has apertures (42) extending from the cavity (14) to the exterior of the body (12) adjacent the wick (40), so that gas produced by evaporation of liquid absorbed on the wick (40) can diffuse out of the arrow.

Abstract: A turf irrigation distribution and reservoir product and method ecosystem employing a substantially continuous mat on the soil surface on which turf is placed or produced, the mat having a primary, lateral water distribution structure which distributes water from a water charging inlet throughout the lateral area to the mat periphery where it is restrained, the water then being distributed vertically above and below the lateral distribution structure.

Abstract: An electric insecticidal apparatus comprising a vessel for storing insecticidal solution, which is oriented in a direction in use; a heating chamber in which the vessel is mounted, said heating chamber containing a heating element; a wick for drawing up the insecticidal solution in the vessel, said wick being provided in the vessel such that the insecticidal solution drawn up by the wick is heated and vaporized by the heating element; an inlet provided at a side of the heating chamber for inserting the vessel into the heating chamber, said vessel being laterally inserted into the heating chamber through the inlet by orienting the vessel in the proper direction; and a guide and holding means for guiding the wick to and holding the wick at a predetermined position at the time of insertion of the vessel into the heating chamber such that the wick confronts the heating element of the heating chamber at a predetermined distance from the heating element, which is provided in the heating chamber.

Abstract: An underground fluid exchange system for control of delivery of fertilization, irrigation and pesticides to and removal from a selected fully encapsulated the turf area of a playing field, including golf course green, having a selected soil profile including a combination turf and topsoil turf segment, a porous soil segment and an impervious soil segment wherein the fluid exchange system comprises a bi-flow porous conduit having uniform porosity that has a selectable exchange rate.

Abstract: An injection hose (1) for concrete construction joints has a substantially liquid-tight base body (2) made of a flexible material such as rubber or plastics that encloses a passage (3). The outer surface (4) of the base body (2) is provided with at least one groove-shaped recess (5) that extends over its whole length. Radial outlets (6) for the liquid injected through the passage (3) are distributed over the length of the recess (5). A strip made of a material that may be compressed under the inner pressure of the injection liquid is received in the recess (5) and covers the outlets (6). A liquid-permeable sheath (8) surrounds the base body (2) and the strip, in the manner of a hose. A single recess (5) extends with a predetermined pitch along a spiral path around the outer surface (4) of the base body (2) or extends parallel to the axis of the passage (3) but has an opening angle of more than 90.degree..

Abstract: Apparatus for dispensing a fine spray of liquid particles comprises a hollow tubular casing (1) whose internal cross section is formed with at least one abutment surface. A tubular liquid source (2) is positioned within the casing (1) with the abutment surface in close contact with the outer surface of the source to provide support thereto. The casing (1) includes a passageway for the flow of air from a mouthpiece (3) positioned at one end of the casing (1) to a nozzle (9) positioned at the other end of the casing (1) into which the discharge end of the liquid source protrudes. The liquid source may comprise a pen formed with a nib (14) of absorbent material.

Abstract: A water-penetrable drip irrigation pipe includes: a buffer tube having a water-penetrable fibrous core member clad in the buffer tube which is lengthwise formed in a main pipe as contiguous to an inside wall of the main pipe, having a plurality of water inlet holes respectively spaced apart and longitudinally formed in a bottom of the buffer tube to communicate with an interior in the main pipe, and a plurality of drip outlet holes longitudinally formed in the main pipe, whereby the water flowing in the interior of the main pipe will penetrate the fibrous core member in the buffer tube to be filtered by and frictionally dampened by the fibrous core member for discharging clean irrigation drips having decreased pressure.

Abstract: The invention concerns an elastic hose with a shaped unsymmetrical cross-section for the delivery of liquids or gases through apertures along the hose, the delivery rate being uniform even over long lengths of hose. The hose is optionally housed in an outer tension-proof cover tube with an open cross-section, in particular a tube open along a generatrix, for the reception of additioned liquids or gases.

Abstract: A release device for slowly releasing vapors of a sprout inhibitor into a small package of potatoes is disclosed. The release device includes a container for holding finely particulate porous media which has absorbed a liquid sprout inhibitor. The container is at least partially porous with respect to sprout inhibitor vapors such that the release device may be utilized to inhibit sprouting of potatoes in small packages during shipments.

Abstract: A capillary system provides water, nutrient solutions and gases such as air to the root zone of plants. The system uses one or more conduits having perforations spaced apart therealong, with the conduits being held in pockets. The pockets are formed with an upper layer of capillary cloth and a lower layer of capillary cloth and/or a water impermeable material. The conduits are provided with devices for connection to a supply of water and the like. In use, the capillary system is buried to an appropriate depth in soil below the plants to be irrigated. The upper layer of capillary cloth is wet by the flow out of the perforations and serves to distribute water evenly to the roots. Valves are optionally provided to control flow through the conduits.

Abstract: This invention relates to the manufacture of flexible porous plastic aeration pipe having an essentially uniform porosity throughout its length. The plastic pipe of this invention has a gas permeable wall of thermoset polymer particles and thermoplastic binder for the particles with a substantially uniform plurality of micropores through the wall of about 0.001 inch to 0.004 inch along its length for diffusion of gas therethrough and transfer to a medium. The thermoset polymer particles have a mesh size of about 60 to about 140 mesh, preferably approximately 80 to 100 mesh. The method of manufacture includes volumetric delivery of thermoset polymer particles and thermoplastic binder particles to a mixing chamber for preblending and then controlled volumetric feeding of the preblend into an extruder to form the porous aeration pipe.

Abstract: A liquid is vaporized by a device having at least one porous substrate exposed to a certain ambient pressure, means for supplying the substrate with liquid in order for it to be loaded with liquid starting from an upstream portion of the substrate, and at least one energy source for heating the substrate so that at least some of the liquid is vaporized. According to the invention, the means for supplying the substrate with liquid may include means for pressurizing the liquid to a pressure greater than ambient pressure, thereby creating a flow-rate greater than the flow-rate induced by capillarity and vaporization of the liquid alone when the substrate is held in a horizontal position. The invention may be applied to the production of water-vaporization equipment, particularly with electrical or gaseous energy supply.

Abstract: An improved scenting system having a frangible vial containing scented liquid disposed within a flexible, moisture-proof sheath member and a wick member having a first end disposed adjacent to the frangible vial and a second end extending from the sheath member, wherein the frangible vial may be broken and the scented liquid released for evaporation by the wick member without the hunter coming into contact with the scented liquid and wherein the scented liquid does not experience unwanted evaporation prior to use.

Abstract: An apparatus for dispensing a fine spray of liquid particles is disclosed. The apparatus comprises a hollow tubular housing and a reservoir pen formed with a nib of absorbent material which is retained within and spaced from the inner wall of the housing. The tubular housing includes at one end a nozzle whose interior defines a converging path and at its other end a mouth piece through which air can be caused to flow through the tubular housing and over the pen to the outlet orifice of the nozzle. An abutment is provided within the housing for locating the pen within the housing with its absorbent nib at least partially within the boundary of the outlet orifice of the nozzle.

Abstract: A process for producing a porous pipe is disclosed and comprises forming an extrudable mixture comprising elastomer particles, binder component and a solid water carrier component having a composition other than the elastomer particles and the binder component and being associated with sufficient water to provide porosity to a porous pipe produced from the mixture; and extruding the extrudable mixture to conditions effective to form the porous pipe.

Abstract: A watering wick for a potted plant comprising an upper part adapted to be forced upwardly through an opening in the bottom of the pot so that it is fully positioned in the growing media. The wick includes a lower tail part which is suspended downwardly into a water reservoir. The wick is made of a hydrophilic material which is resiliently compressible, and is inserted in the pot by a special designed insertion tool.

Abstract: A portable evaporative cooling unit (10) is disclosed. A housing (12) has a front opening (46) and a rear opening (20). Air-permeable water absorption media (22) are disposed across the rear opening (20) of the housing (12). An electric motor driven fan (42) having fan blades (44) is disposed in the front opening (46) of the housing (12) for drawing air through the water absorption media (22). A supply conduit (94) connects a water pump (52) to an elongated horizontal spray bar (64) disposed above the water absorption media (22). The spray bar (64) extends substantially the width of the water absorption media (22) and has a plurality of spaced holes (72) in its upper surface for distributing water. A foam sleeve (68) is disposed around the entire length of the spray bar (64). The foam sleeve (68) absorbs water expelled from the plurality of holes (72) and distributes the water onto the water absorption media (22).

Abstract: An electrostatic device for spraying liquids comprises a nozzle in the form of a wick which is contacted with a reservoir containing the liquid to be sprayed, high electrical potential being applied to the liquid in the vicinity of the spraying tip of the nozzle whereby the liquid is drawn out preponderantly under the influence of electrical forces into ligaments which break up to form a spray of electrically charged liquid droplets. The wick is fabricated from sheet of a resiliently deformable polymeric foam material of open celled structure and an edge of the sheet material is profiled to form a plurality of sites at which liquid ligaments can be produced. Typically a toothed profile is employed in which a plurality of teeth form the sites at which ligament formation occurs.

Abstract: Porous pipe formed of particles of vulcanized rubber dispersed in a binder resin such as linear low density polyethylene preferably having a Melt Index below 1.0 and a broad distribution of molecular weights, is stabilized to reduce degradation by ultraviolet light by dispersing in the binder resin an effective amount of an ultraviolet stabilizer such as 0.1 to 10% by weight of carbon black.

Abstract: A vegetation barrier includes a water permeable container. The container includes salt.

Abstract: Dispenser for foam under pressure, containing a foaming liquid pressurized by a non-liquefied compressed gas, equipped with a dispensing valve (7) having additional gas take-off (8), such that the gas/liquid ratio of the mixture dispensed lies between 95/5 and 99/1 (vol/vol), the dispenser being fitted with a pushbutton (30) which includes a spraying member and an endpiece, the end-piece comprising a case (34) defining an accumulation chamber (40) into which the spraying member sprays the product to be dispensed through a spray nozzle (39) emerging into the accumulation chamber (40), the nozzle (39) having a diameter lying between 0.7 and 2 mm, the chamber (40) being closed by a porous frit (36) constituting, at least in part, a wall of the accumulation chamber (40) opposite that in which the spray nozzle (39) is arranged and located at a distance from the latter lying between 0.5 and 5 mm.

Abstract: The invention relates to a dispenser (1) comprising a container (2) which is to be partly filled with liquid active substance and has a wall that is at least locally resiliently deformable. The dispenser further comprises two immersion tube channels (9, 10) extending from a point adjacent the bottom of the container up to the top of the container (2), one channel terminating in a spray nozzle (8) and the other channel containing a wick (4) or similar absorbent material and terminating in an evaporation space that communicates with the atmosphere. In further elaboration of the invention, the spray nozzle (8), the evaporation space and at least one of the immersion tube channels (9, 10) can be formed as a single moulding which can be click-fitted in the mouth of the container (2) so as to seal it.

Abstract: A flat and thin bladder device is used to cause earthworms to migrate to the earth's surface for easy collection. The bladder is laid flat on the earth's surface and has a maximum thickness between its top wall and bottom wall of not over about 5 centimeters but has area dimensions greater than 1 meter in all directions and not greater than about 4 meters in all directions. The maximum thickness of the bladder is limited by a pattern of spaced connections between the top wall and bottom wall forming the bladder. At least the bottom wall is opaque to block out light under it, and the bottom wall has a plurality of openings that are substantially uniformly distributed for the escape of water from the bladder to earth underlying the bottom wall. Water is introduced to the bladder at a rate about equal to the rate of water escaping from the bottom wall.

Abstract: Porous pipe formed of particles of vulcanized rubber dispersed in a binder resin such as polyethylene are stabilized to reduce degradation by ultraviolet light by dispersing in the binder resin an effective amount of an ultraviolet stabilizer such as 0.1 to 10% by weight of carbon black.

Abstract: A sheet metal atmospheric gas burner capable of a 5:1 turndown ratio is disclosed. The burner is intended for application in instantaneous water heaters and other gas burning appliances having high input modulation requirements. It has a hollow cylindrical burner head fabricated of sheet metal, a single mixer tube, and slotted ports arranged on the vertically-oriented cylinder sidewall. The unique features of the burner are the tabbed slotted port design, the use of fins adjacent to port rows to eliminate flame blowoff and assure quiet burner operation, and the arrangement of ports on the burner head to simultaneously provide good secondary aeration at all inputs and flame carry to all ports at all inputs. The advantages of the burner are its simplicity, low cost, and ease of manufacture, relative to its demanding performance requirements.

Abstract: An irrigation system that combines porous and non-porous tubing in a unified system by means of pressure reducing flow control fittings that connect the lower pressure porous tubing to the higher pressure non-porous distribution tubing. Small holes in discs mounted inside the fittings lower the flow and pressure to the porous tube.

Abstract: An irrigation system that uses porous and non-porous pipe in combination, the porous pipe having a porosity such that the flow of water therethrough is balanced to the flow of water through point source emitters connected to both the porous and non-porous pipes so that simultaneous point source and line source watering is possible.

Abstract: A portable fluid collection and removal apparatus includes an elongated flexible conduit having a generally circular outer wall provided with a perforated flat bottom wall. The inner passageway of the conduit is filled with fluid absorbent material whereby fluid beneath the conduit is drawn upwardly through the perforated bottom wall, into the absorbent material. Wicks leading from the interior fluid absorbent material extend through the flat bottom wall perforations and project outward to expand the area of absorbency by capillary action. Passageways between plural exterior walls transmit auxiliary fluids to warm the conduit to prevent freezing while, a plurality of the conduits may be assembled in a laterally juxtaposed manner to form a blanket.

Abstract: This invention relates to the manufacture of flexible porous irrigation pipe having an essentially uniform porosity throughout its length which is produced by extruding an essentially moisture-free non-homogeneous, mixture of pre-vulcanized elastomeric particles such as reclaimed crumb rubber from vehicle tire treads in major amount and a thermoplastic polymer binder such as low-density polyethylene in minor amount. The mixture is intimately mixed and extruded from an unvented extruder through an annular extruder die at a precisely-controlled temperature and then through a lengthy cooling liquid bath, the rate of pull-off through the extruder die and liquid bath being maintained constant. The leak rate of the fluid delivered from the porous pipe is substantially uniform over a lengthy prescribed dimension exhibiting a delivery variation of less than about 5 percent per unit of length.

Abstract: Apparatus for producing from a bubble solution a beard of long, interconnected bubble chains comprises a hollow elongate tube having opposite ends and a sidewall connecting the opposite ends. The tube has at one end a first portion adapted to receive a gas and at the opposite end a second portion defining at least one aperture extending through the sidewall and in gaseous communication with the first portion. A porous cloth is disposed over and about each of the apertures, the cloth defining a multiplicity of substantially minute interstices for holding thin films of bubble solution. Gas introduced at the one tube end passes through the first tube portion, into the second tube portion, and emerges from the apertures through the bubble solution held in the cloth to form a beard of bubbles extending about and along substantially the entire length of the second portion sidewall.

Abstract: A surface-tension liquid pumping system is provided by one or more arrays of converging solid monofilament fibers or metal wires (strands) spaced apart at an input end to gather liquid, and gathered close together at the opposite end where menisci forms between wetted strands to force liquid in the direction of convergence of the strands. The liquid pumping system is independent of gravity. It is illustrated as being used in a heat pump having a heating box to vaporize liquid and a condensing chamber. Condensed liquid is returned by the pumping system to the heating box where it is again vaporized. A vapor tube carries the vapor to the condensing chamber. In that way, a closed system pumps heat from the heating box to the evaporating chamber and from there radiated to the atmosphere.

Abstract: A header assembly comprises a plurality of substantially V-shaped, slotted troughs disposed in a substantially parallel relationship and interconnected perpendicularly to a manifold. Each trough comprises two substantially parallel, rigid side walls, two rigid end plates and two oblique walls which converge and attach to define an apex of the V-shaped trough. A plurality of alternating spacing elements and slots extends longitudinally along the length of the trough and equidistantly and obliquely along both oblique walls at the apex of the trough. Each trough contains a fiberglass-woven cord extending along the length of the trough and is disposed above the spacing elements and slots and in contact with both oblique walls.

Abstract: A transpiration-protected burner for coal gasification in which a gas such as steam, product synthesis gas or nitrogen is introduced through a porous wall immediately surrounding the openings through which coal and oxygen are introduced.

Abstract: A diffuser for introducing gas in bubbles into liquid held in an aeration tank comprising a body member having a backing surface and passaging extending from a gas inlet to an outlet at the backing surface, and a flexible, gas permeable membrane covering the backing surface and secured at its periphery to the body member in sealing relationship thereto. The membrane is adapted to distend and move away from the backing surface upon delivery of gas under pressure to diffuser, with the gas flowing through the distended portion of the membrane and into the liquid in the form of relatively small gas bubbles, and adapted to collapse into engagement with the backing surface when gas under pressure is not delivered to the diffuser. A check valve comprising a movable valve member on the membrane and a valve seat on the backing surface enables flow of gas into the space between backing surface and the membrane, and blocks flow of liquid into the passaging in the body member.

Abstract: An injection hose for construction joints in concrete structures includes an essentially liquid-impermeable base structure of flexible material such as rubber or synthetic material and defining a passage duct. The base structure has along its length radial openings for the escape of injection liquid from the passage duct and, along its length in the area of the radial openings, at least one longitudinal depression for receiving a strip of a material which is compressible under the pressure of the injection liquid and which covers the openings. A hose of liquid-permeable material surrounds the base structure and strip. A plurality of radial openings are provided in the base structure, and the associated depressions and strips are distributed around the circumference of the base structure angularly symmetrically in relation to the central longitudinal axis.

Abstract: There is disclosed by the present invention a device for increasing the efficiency of the condenser unit of an air conditioner which consists of a predetermined length of copper tubing having perforations punched into it at regular intervals of approximately two inches, and which is covered by a sleeve made up of a woven textile material which is of the length equal to that length of tubing having perforations punched into it. The perforated length of tubing, ensheathed in the sleeve of woven textile material is laid atop the fins, of a condenser unit, which have been bent to accommodate this portion of the device resting on top of the condenser unit. When ambient atmospheric temperature rises above a certain temperature a thermostat causes a valve to allow water to flow into the device, when it flows out of the perforations in the copper tubing and is diffused by the wicking material along the length of the device until the wicking material is saturated.

Abstract: The present disclosure relates to a buck lure dispensing apparatus (10) wherein the apparatus (10) has a receptacle member (14) having a capillary feed tube (25) extending from within the fluid reservoir (16) to a point beneath the fluid reservoir (16). A conformable receptacle holder unit (13) has a tubular length of netting (28) wherein the interstices in the netting (28) are dimensioned to accept the capillary feed tube (25) for the purpose of positioning the outlet (25") of the feed tube relative to the receptacle member (14).

Abstract: A handheld water driven shower massager unit is provided which includes a housing having an internally disposed rotatable nozzle which is caused to rotate by the high velocity discharge of water from the nozzle. By eccentrically weighting the water discharge nozzle, an oscillating vibrational motion is applied to the entire device, thereby providing a massaging effect when pressed against the user. When held away from the user, the unit functions as a source of water spray for cleansing. The performance and characteristics of the unit can be modified through varying the flow rate of water through the unit, by changing the nozzle configuration, or by changing the angle of water discharge from the nozzle. Additionally, various cleansing and massaging pads can be removably attached to the unit in accordance with the needs of the user.

Abstract: An air diffusion device for aerating water with small bubbles, such as for use in clarification ponds, has a perforated air diffusion foil mounted above a tight backing plate. Cross strips are fixed above the foil. The foil is joined tightly at its edges to the solid plate by means of edge strips; cross strips are joined directly to the backing plate. Ballast inlays, preferably extending crosswise, are mounted at intervals in the solid plate to increase the weight of the device.

Abstract: A diffuser for introducing gas in bubbles into liquid held in an aeration tank .[.comprising.]. .Iadd.having .Iaddend.a body member having a backing surface and passaging extending from a gas inlet to an outlet at the backing surface, and a flexible, gas permeable membrane covering the backing surface and secured at its periphery to the body member in sealing relationship thereto. The membrane is .[.adapted to distend.]. .Iadd.distendable .Iaddend.and .[.move.]. .Iadd.moves .Iaddend.away from the backing surface upon delivery of gas under pressure to diffuser, with the gas flowing through the distended portion of the membrane and into the liquid in the form of relatively small gas bubbles, and .[.adapted to collapse.]. .Iadd.collapses .Iaddend.into engagement with the backing surface when gas under pressure is not delivered to the difuser. A check valve .[.comprising.]. .Iadd.has .Iaddend.