Hoardings and scaffoldings are now so scientifically erected as to be little or no inconvenience to foot-passengers. Care must, however, be taken to see that in the erection of a hoarding the doors or gates in it shall not open outwards, and the police should be instructed to prevent carts being backed in and left standing across the footpath. The surveyor must exercise great discretion in the length of time he allows a hoarding to remain; without undue hardship on the builder, he must study at the same time the more important question of the public convenience. (10.) _Dangerous Buildings._-- This is the last, although by no means the least, of the series of “obstructions” I have enumerated. Here, again, very grave responsibility rests with the surveyor to determine what is a dangerous building, and in what manner it shall be rendered safe and secure, for his opinion is apparently legally conclusive on this matter. The following is the clause of the Towns Improvement Clauses Act which deals with ruinous or dangerous buildings: “If any building or wall, or anything affixed thereon, within the limits of the special Act, be deemed by the surveyor of the commissioners to be in a ruinous state and dangerous to passengers or to the occupiers of the neighbouring buildings, such surveyor shall immediately cause a proper hoard or fence to be put up for the protection of passengers,[148] and shall cause notice in writing to be given to the owner of such building or wall, if he be known and resident within the said limits, and shall also cause such notice to be put on the door or other conspicuous part of the said premises, or otherwise to be given to the occupier thereof, if any, requiring such owner or occupier forthwith to take down, secure or repair such building, wall or other thing, as the case shall require. And if such owner or occupier do not begin to repair, take down or secure such building, wall or other thing, within the space of three days after any such notice has been so given or put up as aforesaid, and complete such repairs or taking down or securing as speedily as the nature of the case will admit, the said surveyor may make complaint thereof before two justices to order the owner, or in his default the occupier (if any) of such building, wall, or other thing, to take down, rebuild, repair or otherwise secure, to the satisfaction of such surveyor, the same, or such part thereof as appears to them to be in a dangerous state, within a time to be fixed by such justices. And in case the same be not taken down, repaired, rebuilt or otherwise secured within the time so limited, or if no owner or occupier can be found on whom to serve such order, the commissioners shall with all convenient speed cause all or so much of such building, wall, or other thing as shall be in a ruinous condition and dangerous as aforesaid, to be taken down, repaired, rebuilt or otherwise secured in such manner as shall be