606 TRANSACTIONS OF THE 



Mr. Whetmore instanced some buildings with iron fronts in Chicago, out 

 of which the fronts fell bodily. 



Mr. Garbanati stated that the general idea that a fire-proof building 

 could prevent its contents burning, was absurd. We may preserve the 

 shell, but the contents will burn out. 



Mr. Ayres, in illustration of this, stated that an iron house in San Fran- 

 cisco had its contents burned out, but not a bolt of itself was disturbed, 

 nor could the firemen pull it down. It had to be taken down piece by 

 piece, 



Mr. Reed mentioned that there was an iron light-house, 16 or 18 feet 

 square, constructed on the wharf at Glasgow, and described in the Me- 

 cha7iics'' Magazine for 1824. 



Mr. Johnson stated that Fairbank constructed a mill of sheet iron for 

 Egypt in 1834, and that he had seen a gas-house in London made of iron, 

 before any iron buildings were put up here. 



Mr. Godwin instanced the columns used in Regent's street, London, as 

 specimens of early adaptation of iron to architectural purposes. These 

 columns when taken down in London were imported into New York. He 

 also stated that John L. Mott had used building blocks made of iron. 



Mr. Garbanati instanced Vauxhall and Southwark bridges, London, as 

 specimens of iron building, erected before he was born. 



Mr. Howe called attention to the fact that iron is not the only building 

 material which expands and contracts. Brick walls buckle and spring in 

 consequence of expansion. 



Mr. Baker considered that there was no instance of an iron building 

 standing after its contents had been burned out. 



Dr. Young. — The fii-e might burn out the contents of one floor without 

 injuring the structure ; though cast-iron on cooling suddenly, becomes 

 brittle and unreliable as a material for lintels and beams. 



Mr. Johnson. — In 1822, the original gas-holders or tanks were built of 

 cast-iron, and it is well known that wrought iron has been used for archi- 

 tectural ornamentation for hundreds of years. 



Mr. Seeley. — In considering the subject of building materials, expansion 

 is the most important scientific point to be attended to. A piece of iron a 

 thousand feet in length expands and contracts, say, one inch, with the 

 changes of atmospheric temperature ; and the force with which it expands 

 is irresistable. All materials expand with heat. Professor Horsefield, at 

 the Bunker Hill Monument, found the expansion of the materials of the 

 monument sufficient to disturb his pendulum experiment. The expansion 

 and construction in tubular bridges is calculated and allowed for. The 

 statement made " that rails are laid abutting one against another," is man- 

 ifestly wrong. Their expansion would cause them to twist and bend. 

 When some have been so laid, they have buckled up in the middle. 



Mr, Garvey called attention to the expansion of wood and other materials 

 by hygrometric moisture, which he regarded as vastly more in amount than 

 any expansion likely to occur in iron. He also mentioned the fact that 



