Scientific American Supplement, No. 520, December 19, 1885 | Page 5

wooden sills, with the flooring
boards extending through from one building to the other, are common
occurrences. We frequently find otherwise good doors hung on wooden
jambs by ordinary screws. Sliding doors are frequently hung on to
woodwork, and all attachments are frequently so arranged that they
would be in a very short time destroyed by fire, and cause the door to
fall. In case of fire, a solid iron door offers no resistance to warping. In
an iron lined door, on the contrary, the tendency of the sheet iron to
warp is resisted by the interior wood, and when this burns into charcoal,
it still resists all warping tendencies. I have seen heavily braced solid
iron doors warped and turned after a fire, having proved themselves

utterly worthless. It is needless to say that when wooden doors are lined,
they should be lined on both sides; but frequently we find so-called
fireproof doors lined on one side only.
Good doors are frequently blocked up with stock and other material, so
that in case of fire they could not be closed without great exertion; or
they have been allowed to get out of order, so that in case of fire they
are useless. This has been so common that it has given rise to the
jocular expression of insurance men, when they are told that a fire door
exists between the two buildings, "Warranted to be open in case of
fire." The strictest regulations should exist in regard to closing the fire
doors nightly. Frequently we find that although the fire door, and its
different parts, are correctly made, there are openings in the wall which
would allow the fire to travel from one building to the other, such as
unprotected belt and shaft holes. That a fire door may be effective, it
must be hung to the only opening in the wall.
The greatest care must be exercised to keep joists from extending too
far into the wall, so as not to touch the joists of the adjacent building,
which would transmit the flames from one building to the other in case
of fire. A good stone sill should be placed under the door, and the floor
thereby entirely cut. Sills should be raised about one and a half inches
above the level of the floor, in order to accomplish the necessary
flooding of the same. If stock must be wheeled from one building to the
other, the sill can be readily beveled on both sides of the wall, allowing
the wheels to pass readily over it. Lintels should consist of good brick
arches. When swing doors are used, they should be hung on good iron
staples, well walled into the masonry, and the staples so arranged that
the door will have a tendency to close by its own weight. The door
should consist of two layers of good one and a quarter inch boards,
nailed crosswise, well nailed together and braced, and then covered
with sheet iron nailed on, or if of sheet tin, flanged, soldered, and
nailed. Particular care should be taken to insert plenty of nails, not only
along the edge of the door, but crosswise in all directions. I have seen
cases, where the entire covering had been ripped off through the
warping tendencies of the sheet iron.
The hinges on these doors should be good strap hinges, tightly fastened
to the door by bolts extending through it, and secured by nuts on the
other side. Good latches which keep the door in position when closed

should always be provided. In no case should the door be provided with
a spring lock which cannot be freely opened, as employes might
thereby be confined in a burning room.
Sliding doors should be hung on wrought iron runways, fastened tightly
to the wall. Wooden runways iron lined, which we frequently see, are
not good, as the charring of the wood in the interior causes them to
weaken and the doors to drop. Runways should be on an incline, so that
the door when not held open will close itself. Care must be taken to
have a stop provided in the runway, so that the doors may not, as I have
frequently seen them, overrun the opening which it is to protect. Doors
should overlap the edges of the openings on all sides. Large projecting
jambs should never be used.
All doors contained in "fire walls" should have springs or weights
attached to them, so as to be at all times closed. Fire doors can be shut
automatically by a weight, which is released by the melting of a piece
of very fusible solder employed for this purpose. So sensitive is this
solder that a fire door has been made to shut by holding a lamp some
distance beneath the