Abstract: The horn housing may comprise an inner metal shell in the shape of a hexagonal box open at one end fitting into a similarly shaped outer dense solid box similarly open at one end. Space between the inner and the outer boxes being filled by a low density sound absorbing filler, and the inner box being connected to the outer box by vibration absorbing bolts. The outer box is mounted to a structure by vibration absorbing mounting brackets. When a high decibel horn or siren is mounted in the inner box to directed sound through the opening, most of the sound propagating sideways towards the structure is absorbed by the housing increasing the comfort level of passengers or crew inside the structure.

Abstract: An elongated discharge lamp which is particularly intended for use in photo-chemical reaction processes. The discharge tube of the lamp is supported at its ends by two end mountings, one of which carries the input terminals for the lamp. A conductor extending along the length of the discharge tube joins one of the terminals to the electrode at the remote end of the tube, and the tube and conductor are separately enclosed in respective transparent tubular envelopes sealed to the end mountings at their ends.A liquid-cooling jacket is provided, cooling liquid being circulated therethrough by means of a tube of transparent material supported in the end mountings.