Some persons have an idea that a round brush will not sweep a square flue, but in the annexed diagram, the diameter of the brush B B is compared with the chimney A, which clearly shows that the whalebone of which the brush is composed, is forced into every part of the flue, and being repeatedly thrust up and down, must sweep it effectually. A bricklayer might here observe, “Admitting you can sweep chimneys with the machine, how would you core them?” More effectually and with greater facility than boys can possibly do it. Chimneys that are straight, or nearly so, do not require coring, and the rubbish that falls on the diagonal part of the flue, where the angles are obtuse, can easily be dislodged by a stiff brush attached to the machine, and introduced into the top of the chimney. At right angles, or when they are nearly so, an opening should be left six or nine inches square at the angle: and when the chimneys are finished, the core can be extracted in five minutes, which a boy would not be able to accomplish in several hours or days. It has frequently occurred, that a boy could not succeed in clearing the chimney of the core, and an opening has been made for that purpose at last. This plan was adopted with success at Buckingham Palace, the London University, Post Office, St. Martin’s-le-grand, and Fishmonger’s Hall. It is altogether unreasonable to employ boys to core chimneys at the imminent danger of their lives, when it can be so easily done as described, and at so much less expense. A builder might remark, “You have explained how you can core chimneys without a climbing-boy, but how would you place a brick or stop a crevice in any part of a flue, if required, without a climbing-boy?” On the first appearance of smoke, I would advise that a carpenter should remove the board that forms the plinth, and one or two flooring boards, when the defect would at once be discovered. A bricklayer would soon make it sound and secure; the boards and plinth might then be replaced, and all would be safe, and no further annoyance experienced. A good machine, in the hands of a person who well understands the use of it, will not meet with one chimney in a thousand that it cannot effectually sweep. Several persons of this description, who have served their time as chimney-sweepers, are employed in the use of the machine, by the Agents of the Society for Superseding Climbing-boys. N.B. The provisions of the late “Chimney-sweepers Regulation Act” were entirely against the opinion and advice of the above Society, and the obnoxious clause, prohibiting chimney-sweepers from calling in the streets, was inserted at the suggestion of the principal master chimney-sweepers themselves. The Society will never be satisfied till the use of climbing-boys is done away with altogether, being a cruel and unnecessary method. PRICES OF MACHINERY, _Manufactured by Joseph Glass, No. 2, Moor-lane, Fore-street_. Cane Machines, with chimney cloth complete:--