Mr Fairbairn on Fireproof Warehouses. 115 
to impress them forcibly upon the public mind, that the prin- 
ciple is the same, however much they may vary in their ratio 
of strength. 
In treating of the strength of columns, I have endeavoured 
to establish principles which are not generally known, but 
which are proved to be fixed and determined laws affecting 
the increase or diminution of strength according as the ends 
are made round or flat. 
In order, therefore, to avoid error in the construction of 
buildings adapted for the support of heavy weights, it will be 
of some value to know, that the strength of pillars can be in- 
creased according as their ends are shaped, in the numerical 
ratio of 1, 2, 3. 
Having investigated the subject at some length, it may be 
necessary, before closing the report, to advert to a circum- 
stance which appears to excite alarm, and increase the fears 
of individuals, respecting the safety of iron beams and brick 
arches as a perfectly fireproof structure. It has been alleged, 
that in case of fire in any of the lower rooms in a warehouse, 
that the intense heat generated by rapid combustion might 
melt the iron columns, and bring the whole edifice to the 
ground.* This is a possible, but a very improbable case, as 
an event of this kind could never happen provided the pre- 
cautions enforced and inculcated in this inquiry be duly and 
properly observed. It is true that negligence of construction 
on one hand, and want of care in the management on the 
other, might entail risk and loss to an enormous extent ; but 
* There is only one instance which has come to my knowledge of a 
fireproof building being injured by the melting of the columns, and that 
was at the works of Messrs Sharp, Roberts, and Co., in Manchester, 
where the pillars were fixed between the boilers of the steam-engine, 
and having a large quantity of wood piled round them on the top of the 
boiler, for the purpose of drying, the heat became so intense as to cause 
them to bend, and ultimately break. In this case, the front of the 
boiler-house was open, with a thorough draft direct across the building, 
which generated a most intense heat, and caused the whole room to act 
as a reverberating furnace. Viewing the subject in this light, it cannot 
be considered analogous to a warehouse efficiently secured against the 
admission of atmospheric air, 
