It is doubtful, however, if trade signs projecting at such a height as not to be “an obstruction to the safe and convenient passage along any street” can be removed under this section, however unsightly they may be, nor does it appear that flag poles or flags can be ordered to be removed when at such a height as to cause no obstruction. The following clause, however, of the Public Health Act 1875 affects the question of new projections much more closely. “It shall not be lawful in any urban district, without the written consent of the urban authority, to bring forward any house or building forming part of any street or any part thereof, beyond the front wall of the house or building on either side thereof, nor to build any addition thereto beyond the front of the house or building on either side of the same. Any person offending against this enactment shall be liable to a penalty not exceeding 40_s._ for every day during which the offence is continued after written notice in this behalf from the urban authority” (38 & 39 Vic. c. 55, s. 156). Here some difficulty is frequently experienced as to the question if the building has really been brought beyond the common line of neighbouring buildings, especially where the houses are detached; but it is apparently left to the tribunal before whom the case is heard to decide this point, and the surveyor can only give his evidence, as in many other cases, to the best of his ability and knowledge, and trust to obtaining a verdict in his favour. With regard to obstructions erected before the passing of the special Act, the commissioners may cause the same to be removed or altered as they think fit-- “Provided that they give notice of such intended removal or alteration to the occupier[137] of the house or building against or in front of which such alteration or removal is begun; and if such obstructions or projections shall have been lawfully made, they shall make reasonable compensation to every person who suffers damage by such removal or alteration.”[138] Here the words “_reasonable_ compensation” are difficult of construction and lead frequently to long litigation. (3.) _Doors or Gates opening outwards._--