AMERICAN INSTITUTE. C05 



they have been wholly inadequate to overcome the much greater 

 expansion from artificial heat in contiguous conflagrations. Iron 

 buildings, as usually constructed, although expressly designed to 

 resist conflagrations in compact cities, have been wholly ineffec- 

 tual for this purpose. It was found in the great fires at San Fran- 

 cisco that the iron columns and framework of buildings were 

 expanded, and thus warped and thrown out of line, by the heat of 

 fires across the streets, and that the buildings were ruined even 

 before contact of the flames." 



From these remarks it may be inferred, that their author either 

 did not know that there was such a thing as cast-iron buildings 

 in existence, or that there was any difference between them and 

 those made of wrought iron. The houses of San Francisco, which 

 are described as shriveling like paper before they came in contact 

 with the flames, were built of sheet-iron, either plain or corru- 

 gated; nailed, in most cases, to wooden posts; or, like the better 

 class of English iron houses, riveted to cast-iron columns, and 

 thence ignorantly described as cast-iron buildings. 



Cast-iron houses are perfectly fire-proof. Were such a building 

 as Mr. Bogardus's factory filled with the most combustible goods, 

 such as cotton or resin, and the entire interior in flames at once, 

 until the whole was consumed, the building itself would remain 

 firm and unimpaired. Some have said that the columns might 

 melt, and thus precipitate, the whole; but this is simply an ab- 

 surdity, said without reflection : for, it is well known, not only a 

 high and intense heat, but the use of a blast, as required to reduce 

 iron to a molten state; and never yet, in any conflagration, has it 

 been found melted, except in pieces of minute dimensions, and 

 in such situation that the current of the flames created around 

 them an artificial blast. Others compare iron houses to stoves, 

 and tell us that if certain parts be made red hot, and cold water 

 then tlu-own upon them, it will warp and crack the metal : but 

 this only shows a mechanical defect in their construction; for it is 

 quite possible so to construct a stove that it would stand such a 

 test without damage, though it were repeated many times a day, 

 for years. And that the several parts of Mr. Bogardus's buildings 

 are carefully modeled so as to run no risk of this disaster, he has 

 ascertained by direct experiment for this purpose. 



This experiment has been repeatedly verified since in the fol- 

 lowing way. It has sometimes happened that his columns would 

 be found warped when they came from the foundry. To remedy 

 this defect, he made the column red hot; and whilst in this con- 



