St. Paul daily globe. [volume] (Saint Paul, Minn.) 1884-1896, 1884-03-12
DYNAMITE.

66DLOSfTe---HObC az IS lHUnNTUcruTe0.
In 1916 Ascagne Sobrero, then pupil il
the laboratory of Pelouze, the eminent French
chemist, made many experiments, and a
length produced explosive compounds from
dextrine, mannite, cane-sugar, glycerine
The discovery caused a sensation among thu
scientists Its liability to explode premature
" for a long time prevented its being put Il
any practical use. About 1853 two mining
engineers, Henry and Alfred Noble, began
to experiment with nitro-glycerint
as blasting agent. 1t proved
to be SO effective and econom
ical that they took out patents in different
counties for an explosive compound similar
TO dynamite now so widely known, of which
they claimed to be the inventors The honor
of the discovery, however, clearly belongs tc
Sobrero.
Since the discovery made by Sobrero ex
periments have demonstrated that nitro
glycerine in some of its PREPARATIONS can be
used with comparative safety. Of these pre-
partitions dynamite is the best Nitro-glycerine
is itself formed by the action of nitric
acid upon glycerine at low temperature.
In dynamite the absorbent is usu-
ally natural silicious earth Deposits OF
this silicious earth are found in many places,
notably in Hanover From the Hanover
earth the original dynamite was made. The
silicious earth is fine white powder, com
posed of the skeletons of microscopic ami
mails Cnfusoria): It has a high absorptive
power, being capable of taking up from Two
to three times its weight of nitro-glycerine
without becoming pasty. Artificially-pre-
pared SILICA has been proposed as substi-
tutc for the natural earth by Prof. Walter N.
tod tote In
station at Newport, where it has
been used with good results. This
silica is prepared by precipitating it from a
solution of sodium silicate (water-glass) by
sulphuric acid washing and drying. Its alb
sorbent power is little less than that of the
natural earth, but it retains the nitro-glycer-
inc very well. The process of making dyna-
mite is very simple. The nytro-glycerine is
mixed with the dry, fine powder in a leaden
vessel with wooden spatulas.
Dynamite, ''says Prof. Hill, "has brown
color, and resembles in appearance moist
brown sugar. 1t usually contains from &C
to IS per cent. of nitro-glycerine. In this
country dynamite is made and sold under
the name of giant powder. The explosive
properties of dynamite are those of the nitro
glycerine contained in it, as the alb
sorbent is an inert body. 1t freezes at the
same temperature as its nitro-glycerine to a
white mass. If solidly frozen it cannot be
fired, but if loose and pulvernlent it can be
exploded, although with diminished violence.
1t can be thawed by placing the vessel con-
tanning it in hot water. The keeping quail
ties of dynamite are those Of the nitro-glycer-
inc it is made from. 1t is safer because il
avoids the liquid condition, and from its
softness it will bear blows much better. EXu-
dation must be guarded against. Therefore
it must not contain too much nitro
glycerine, especially if it is liable
to be exposed to comparatively high
temperatures, which tend to make the nitro
glycerine more fluid, and consequently less
easily retained. The firing point of dyna-
mite is the same as it's nitro-glycerine. If
flame is applied to it it takes fire and burns
with a strong flame, leaving a residue of
silica. 1t is not sensitive to friction or mod
crate percussion"
The explosive force of dynamite is of
course, that of nitro glycerine contained in
it. If it contains Is per cent. its compare
tive force may be approximately stated at six
times that of gunpowder, weight for weight.
Dynamite, proper, contains only nitro-glycer-
inc and the slicious absorbent Mixtures
containing other substances are some
times included under the same name.
The true dynamite is often called dynamite
No. l." and others dynamite No 81 or re-
ceive fanciful names. All these mixtures
contain less nitro gycerine than the No. l.,
so that they cost less per pound, but, of
course, they are proportionately less power
full. The following are varieties of No. 2
dynamite made in England:
Per cent. Per cent.
Nitrate of soda. SO. 90 Nitrate of potash II 90
Parattine. ZOO Paratfine. ..... 90
Charcoal or coal Charcoal. -. 10. 90
DUST. ....... 400 Nitro glycerine 90
Nitro glycerine. 1000
Total. 100 90
Total. go. 10000
1t is hard to see any advantage in these
mixtures, except that they are cheaper and
might be applied to uses where the great VOL
ence of the larger amount of nitro-glycerine
is not needed, and yet sharper explosive
than powder is wanted. 1t is improbable
that any useful effect is obtained from any
other ingredient than the nitro-glycerine.
Those obtaining deliquescent salts (nitrate Of
soda, for example,) are Objectionable from
their liability to emulation. All of them will be
injured by water, which dissolves the salts,
which are the principal ingredients. tits easy to
see that the number of such mixtures that
might be made is very great, for almost any
dry salt or powder may be taken as an alb
sorbent. No special value would attach to
any of them. The only requisites would
be that the absorbents should not exert any
injurious action, and that no more nitro
glycerine should be present than could be
perfectly retained at the highest temperature
that would probably be experienced.
The explosion of nitro-glycerine is so
rapid and violent that the air above it has no
time to move away, but acts like solid !;
hence it will act downwards when placed
upon the surface of rock.
NdrdJ Plumber.