The Democratic advocate., 1882-05-13
Is Flour Explosive 2

The terrible mill explosions in different
parts ofthe world, particularly in Minneapolis,
have appeared mysterious in their origin.
Perhaps the theory of Prof. T. W. Tobin, ad-
vanced at the reception of the Millers' Asso-
citation by the Polytechnic Society of Louis
vile on Thursday last, may be sufficient to
explain the cause of some of these explosions.
Certainly nothing so plausible has been ad
vanced to account for the sudden destruction
of the mills in Glasgow, Scotland. and in
Minneapolis. and millers may well heed the
warning that there is a giant force locked up
in the familiar wheat berry which, when the
right time arrives, can, without moments
warning, convert scene of thrift and indus
try into one of desoation.
There are certain conditions in which the
JleSt substances become the most danger
Gus. Hydrogen heated with air evolves a vio-
lent explosive force. Chlorate of potash will
not ignite, and starch extinguishes a taper
that is plunged into it but mixture of the
two substances is not only highly combustible,
but explosive. The fine dust from the wood
of a furniture factory in a mass will not take
fire readily. but if a heap of it is charged with
air from a bellows flame will leap out of it
when lighted taper is applied; and the same
is true of fine patent flour.
The minute spores of the club moss form
an almost impalpable powder, yet it is highly
iniammable, and is often used in the manu-
facture of fireworks and the artificial repre-
sentation of lightning. 1t is maintained by
Prof. Tobin that the dust on the outside of the
wheat grain contains similar organic spores,
which render the dust shaft and dust rooms
the most dangerous places in mills. To illus
trate the explosiveness of -four the Professor
has devised -four gun, composed of pyra-
midal shaft and barrel, with gas burner at
its base, air holes in its sides, and hopper at
the top. At the bottom of the hopper is a
movable shaft operated by an outside trig
ger The hopper is loaded with -four or mill
dust. and the mouth of the gun Is covered
with a stout newspaper. The lighted gas ere
ates an upward draught and heats the air
When the trigger is pulled and the dust or
-four is charged with the heated air, tre-
mendous explosion follows, the building trem-
bles with the shock, the paper is blown to
( shreds, and takes fire by the great heat gene
rated in this way.
( Upon the dav of the destruction of the three
Minneapolis mills, they had been running all
/ day to the fullest capacity the machinery
( was heated and the air was charged with dust,
/ for the wheat of that year was exceptionally
I hard aud dense. \ workman carried an open
Z laatern to the dust shoot to examine some
machinery that had become defective. A
drssught Of air rushing Iva carried before IL the
flame and the dust. and in q few seconds,
after three tremendous de;onations. flames
Ieaped up from the mass OF ruins Of three
great structures.
II Is we'll. l.known that the air of -four mill
is very dry. az Is demonstrated by the elee-
tricity generated by the belts, and that fine
-four will rapidly deprive the atmosphere o.
iis natural humidity. This fact, taken with
the others adduced, renders valuable the ad
vice that the shafts Of mills should be provid
ed with wet hulb Thermometers, and that whel
the air becomes abnormally dry, live steam
should be injected from the boilers into th'
mill and as a moist atmosphere Is held b.
competent millers 20 be conducive to makins
q whiter and better kind Of -four, there seem
% b. no objection 10 this remedy