Abstract: A connector for wires comprises a body (20) having through passage (21) adapted to receive a pair of oppositely directed wire end portions (22A, 22B) in close lengthwise relationship with each other, channels (23A, 23B) within the body (20) one to each side of the through passage acutely inclined to and, at their inner ends, breaking into the through passage, and wedge structure (24A, 24B) within the channels adapted upon attempted withdrawal of either of the wire end portions (22A, 22B) from the through passage (21) to urge the wires therebetween forcibly towards each other, whereby friction secures them firmly in the connector.

Abstract: A device for holding photosensitive material during light exposure which comprises two planar frames of equal size, each of which has two parallel walls and rounded corners, one frame at least being open between its four walls, each frame carrying around its peripheral walls a band of resilient material of rounded cross-section which when the device is in the non-use state is so mounted that part of the band is held above walls of the frame, the sides of each frame being bevelled outwards, together with means to hold in position the two frames separated from each other with the bands of resilient material facing each other, means to force the two frames together so that the bands contact each other substantially over their entire length and force each other down the walls of each frame and means to hold securely the two frames in this position.The device is of particular use for exposing holographic film material.