Abstract: A spool and wedge assembly for securing replaceable cutting teeth or cutting elements to the nose portions of earth moving buckets. The spool and wedge assembly comprises first and second parallel longitudinally extended spool elements, which are transversely displaced apart to engage the aligned side walls of the securing element receiving apertures, and, first and second wedge shaped elements. The wedge and spool elements are interconnected by a longitudinally disposed screw threaded bolt mechanism which is tightened to draw the first and second wedge elements together while forcing the first and second spool elements apart, such that the cutting teeth are locked in position.

Abstract: A device for detecting the presence of a predetermined reactant in a fluid suspected of containing the same which comprises a pyroelectric film having a first and a second surface, a first electrode in contact with a portion of the first surface of said pyroelectric film, a second electrode in contact with a portion of the first surface of said pyroelectric film, said first and said second electrodes being proximate to but electrically insulated from each other, an infra-red transparent third electrode having a first and second surface, said first surface being in contact with the second surface of said film, methods of making such a device and methods of utilizing same.