Abstract: A device for simulating electrical characteristics of an electrical, electronic or electromechanical component comprising circuitry (21) adapted to reproduce electrical characteristics which are produced by, or may be sensed in, the component, the device (1) being configured so as to substantially resemble the component in appearance and/or size. The device may have two substantially flat opposed surfaces (3,27), one of which carries a picture (5)of the component and the other a sectional view through the component to illustrate its technical construction or operation, and/or other data relating to the component. A kit may be provided comprising a number of such devices each to simulate a component forming part of an equipment or system so as to simulate the electrical characteristics and/or performance of the equipment or system.

Abstract: A map comprising a concertina-folded sheet printed on both sides of the sheet, the markings on the two sides representing contiguous areas and being disposed so that a line on the map representing a route passing from one such area to the other extends around an edge of the sheet which lies at right angles to the concertina folds, the sheet having on an outer end flaps two key maps, inverted with respect to each other and corresponding respectively to the two sides of the sheet, to direct the user to the desired part of the map by means of indicia associated with the key maps which correspond to indicia provided upon the edge folds of the map.