Abstract: A manifold formed of a plastic main body member and a plurality of tubular metal inserts. The metal inserts are received in bosses formed at longitudinally spaced locations along the plastic main body member and provide communication therethrough with the interior of the main body member. Each insert includes a wrenching portion at its inner end which coacts with the adjacent material of the plastic member to preclude turning of the insert in the respective boss upon torquing of a threaded member into the insert and each insert further includes an annular groove adjacent the wrenching portion to preclude axial movement of the insert within the boss. A method of forming the manifold is also disclosed in which the inserts are respectively positioned on a plurality of longitudinally spaced upstanding pins on a lower mold half to locate the inserts within the mold during the molding process.

Abstract: A teaching apparatus especially for dyslectic students of the type wherein a platen carrying the work lesson is movable between a raised position in which the indicia on the worksheet is readily traceable by a student on tracing paper positioned over a window above the platen to a lowered position where the indicia on the worksheet gradually becomes indiscernible to the student. A bellows is moved to a collapsed position in response to movement of the platen to its raised position and the bellows is operative when extended to move the platen to its lowered position. Valve means are provided to selectively control the rate at which air is allowed to move back into the collapsed bellows to thereby control the rate of extension of the bellows and the rate at which the platen returns to its lowered position.