Abstract: An ice hockey skate blade has a top edge, a skating edge, and a toe portion. The skating edge has a gliding portion behind the toe portion. The gliding portion width is less than the top edge of the blade and the toe portion of the blade. The front toe portion of the blade allows contact with the ice and has a width equivalent to standard hockey ice skate widths, while the gliding portion of the blade behind the toe section has a width corresponding to ice skate racing blades.

Abstract: A skate boot is described which includes an overlapping tension strap extending from the medial side of the outer sole to the medial lacing band, and the lacing passes through eyelets provided in the tension strap. The lacing bands are arranged such that in the bottom portion thereof below the tarsis, they are symmetrical to a line drawn approximately over the highest ridge of the dorsal of the foot, that is, at the first or second metatarsal and above the tarsis they are symmetrical with the axis of the anterior tibial tendon so that the lacing is evenly distributed on either side of the highest ridge of the foot in these areas. A liner is provided in the rear part of the boot such as to provide lateral support. The liner is relatively stiff but is provided with cutouts allowing the boot to flex in the dorsal-plantar flexion direction.

Abstract: An anti-jackknife mechanism for a tractor-trailer arrangement wherein a stop member on the tractor and an assembly on the trailer can be positioned relative to each other so that an angular change between the tractor and trailer from its normally longitudinally aligned position is resiliently resisted and such resilient resistance is under the control of fluid motors.

Abstract: A solid anhydrous crystalline compound of the formula H.sub.3 PO.sub.4 [(CH.sub.3).sub.2 CH].sub.2 O. The invention also provides a method of preparing phosphoric acid by evaporating diisopropyl ether off said anhydrous crystalline compound under reduced pressure.

Abstract: A thermostatically controlled safety heater for upright immersion in an aquarium includes a housing with an axially extending, heat-transmitting tube forming a chamber in which an electric heating element is disposed in radially spaced relation from the tube. The radial space between the tube and element, over substantially the axial length of the element, is filled with a heat conducting, thermally expansible liquid. An actuator device including a linearly movable plunger reactive to thermal expansion of the liquid is provided for opening and closing a switch in circuit with the heating element for maintaining the heater at a desired temperature. A hunting tendency of the switch contacts is overcome by providing a damping medium in the form of an air space having a volume less than about ten per cent of the volume of liquid between the plunger and the liquid. An expansible sealing diaphragm supports the plunger and isolates the liquid to the portion of the tube in which the heating element is disposed.

Abstract: A solid anhydrous 1:1 molar compound of phosphoric acid and diisopropyl ether is prepared from a mixture of the ether and phosphoric acid in a molar ratio (R:1) of 0.6:1 to 1.4:1 at a temperature at least as low as the crystallization temperature (T.degree.C) governed by the relationship T = 25(1.2-R). Treatment of the compound with water or a base produces purified acid or a phosphate respectively.