New-York tribune., 1868-05-16
FIRE.PRooF FLOORING EXPERIMENT.

X. Hoe e. Co. are eniarging their works on
Sheriff Grandst. During the past four days they
have been making number Of interesting experiments
with view OF rendering the ordinary wood flooring
proof and adopting the method that should prove the
successful In the first experiment square section
Of beams, iOxiO feet raised about six feet from the
ground athed the under side with strips OF pine
half an inch thick nailed from two inches apart
These served retain ceiling OF plaster OF paris spread
under the beams to quarter Of inch below the strips
and half inch thick between the beams and above the
sheetron tubes OF oval form. but CIR.
cular or rectangular tubes according as
the spaces between the beams required IT, would
equally WE'LL the object being 10 nclose the bulk OF the
space between the beams The remaining space between
then ed the upper side OF the beams covered with
the plaster OF Pa.is, completely cuveloping the tubes
After allowing sufficient time for the plaster to set the
dry and hard; when fierce fire was lighted within
SSr oes The ~ trs result OF he after wns that the
plaster the undersde had cracked on In places, and
not st all injured and the are had any opening
throfgh the floor above, which never so heated
but tha. one could have stood barefooted on IT without
In the second experiment. thin sheets OF iron ermped
present series OF with the large parts
the beams. This plastcred with scratch aud plain
coat of lime and sand and on this an additional coat OF
the fire lighted and kept up as before hours aud
the result that the plaster cracked of and beams
began TO burn, whereupon the fre was oxtinguished
The third experiment proved moro successful Strips
Of pine an inch wide by an inch thick. were nailed
engthwse the under side OF the beams throughout
their length. Thin sheets OF iron, No. Wire Gauge,
then fastened upon them, the strips keeping the
sheet iron distance OF inch from the beams Plaster
OF Paris TO the depth II inches poured the sheet
ron and the sides and top Of the beam smeared with H.
and when conveniently plastic rounded 20 some inches
up the sdes After the plaster had become set the floor
boards xed. the fro lighted and kept up before
for n hours the result that In few places only the
beams we're slightly smoked but other indications Of
fre were visible ..t
The fourth and last trial, conducted the prnc
pie as the third concluded yesterday In this pro
vision was made against fire from the upper well az
lower side by fastening thin sheets Of iron the top OF
the beams and spreading layer OF Plaster OF Paris
inch think the sheet before laying the wooden
hoorng For three hours intense heat was kept up
directly under this flooring Then another nre was but
on the noor above After burning for three hours the
nre was eItngushed and an examination made. which
proved the experiment 10 be complete success The
following figures show the cost OF this Improvement:
Cost OF Orlo H. OF 1reproo flooring prepared AZ per ex
pertinent over and above the cost OF ordinary hoorng
average thickness Of plaster OF Paris u n equal To- l2
cubic feet ~ the square Of i0xio feet equal TO three bar
res OF plaster AT S. o. IS sheet iron on top ana bot
tom. 200ssqnare feet No Al wire gauge, $50 n, at &c.
ti6 so nasons aud carpenters time hours each, u 76
total cost for square 0x0 feet $50 TO- The cost for fire
PROOF moor i0ox2o Feet less walls, would be 1s 10 moro
than the cost OF the common combusble flooring The
cost OF brick ana iron beam fire proof building Is moro
than double tho coat OF brick aud wood structure.