606 TRANSACTIONS OF THE 



dition, by means of powerful screws, forced the parts, not only 

 to the position required, but in some cases, as much as six inches 

 beyond it : yet, after cooling, he has invariably found them to be 

 warped, exactly as at first. It may be here added, that, in his 

 later experiments, he endeavored to secure the set of the column, 

 by dashing cold water upon it when red-hot, but equally without 

 success. 



It is desirable, in most cases, that the floorings and partitions 

 should be also fire-proof; so that, should a fire occur, it may be 

 confined to the room in which it originated. This may be accom- 

 plished by various well known devices, extensively practiced in 

 Europe, but too much neglected in our country. Mr. Bogardus 

 has also devised for this purpose, and secured by letters patent, 

 a plan of iron flooring, to be supported by Cooper's iron bejims, 

 or by his own new sectional truss girders, which he is now taking 

 measures to patent, and which may be seen in use in the build- 

 ings of Messrs. Harper & Brothers, the well known publishers. 

 These girders, besides having other advantages, can sustain a 

 heavier load than any others of the same weight yet known, and 

 are therefore more economical. And to those who prefer a wood- 

 en floor, Mr. Bogardus offers another plan, in which the flooring 

 rests upon the aforesaid truss girders, in combination with a sub- 

 stratum of solid brick-work, and a net-work of iron wire as a 

 substitute for laths. Of this latter plan a model is now on exhibi- 

 tion at his office. 



Cast-iron buildings are also perfectly safe during thunder storms; 

 no accident from the electric fluid can happen to any person with- 

 in them. The metal being a good conductor, and presenting so 

 great a mass to the overcharged clouds, conveys all the electricity 

 silently to the earth, and thus obviates all danger from disruptive 

 discharges. An iron building, for this reason, requires no light- 

 ning rods, because it is a huge conductor itself. This is a feature 

 deserving consideration; for many ordinary buildings with rods 

 attached to them, have been struck with lightning, whereby a 

 number of persons have lost their lives ; accidents which can 

 never occur in cast-iron buildings. In them the intensity current 

 is instantly diff'used throughout the entire mass, and thus changed 

 into a current of quantity : so that, in any one part, the electricity 

 must be very feeble, and therefore not dangerous to life. 



Every style of architecture, and every design the artist can con- 

 ceive, however plain or however complicated, can be executed 

 exactly in cast-iron; and, in consequence of its having greater 



