Phenix gazette. [volume] (Alexandria [D.C.]) 1825-1833, 1831-08-24


and by means of levers and pulleys, il NAV =
made to act at any distance which NAV be -, :"
ferable. There is no limit to the numbe,r e
charges which may be thus ignited, excen,iD y
those assigned, by economy, to the size Of n.
apparatus employed.
These remarks have reference TO the priue;,
and highly important object Of Mr. Sbaw's m
ject; which is, to ignite at once great numb 1s
Of charges in as many perforatiOns 50 drilled IN !,
rock as TO cooperate simultaneously in the sms
plan. Ry.these means it is conceived that ~.
stone may be separated into large prismatic I .,
tabular masses, instead Of being reduced 70 j.,
regular fragments of an inferior size.
TIE object to which propose now to c,,i
attention more particularly is modification os
the common process Of blasting by one cbaros
which renders that process perfectly safe. o.
This part Of the subject shall introduce br
promising that almost all the accidents, which h,y,
taken place in blasting rocks have occurred in ons
Of the three following modes:
LIST. The explosion has taken place premature.
~, before the operator has had time to retire
End. 4 premature explosion has euSued (ror
spark produced by tho collision arising from r,r
ming into the oritice Of the pertoraton, cont,s
ing the powder, the brick dust or sand empJOv,I
to close it.
Sid. The fire not reaching the charge after III,
expiration Of period unusually long and a,
operator returning to ascertain the cause Of II,
supposed failure an explosion ensucs when h.
so near as to suiier BY il. as in the instance re
Norristown, lately published.
The means OF communicating ignition. 10 who,
| have resorted, arc as follows
Three iron wires, of which one is the smalIs,,
size used for wire cause. the others of the 81.
NO. 24) used by bottlers. are firmly twisted "a
gether. This IS best accomplished by attacHp,
them 70 the centre of the mandrll OF lathe. wbit,
is made to revUye while the other ends q III
wires are held by vice, SO as to keep them in
proper state of tension. After being thus tu,-
ed small portion is UNFINISHED. 50 as to get
and divide the larger wires by pair Of nipper
In this way the smaller wire is rendered the so,
mean of metallic connection between the large
ones. These are tied 10 a saw kerf, or made il
small piece Of dog wood, to secure them fra
working; which if permitted, would cause b, |
smaller wire to break apart. At one end, d.
twist formed Of the wires is soldered to the M
tom of tin tube of size to fill the perfOrstS
in the rock to such height as may be deems.
proper. This tube being supplied with gun pos
der, the Orifice is closed with cork, perloraet
so that the twisted wire may pass out through
without touching the tube, at any point above tr
where the finer PORTION alone intervenes. TU&
outside of the tube copper wire about No. Il
is soldered, long enough to extend to stout COP
per wire proceeding from one Of the poles Of
galvanic defagrator or calorimotor. The wrs
passing through the cork, from the inside Of tt
tube, is in like manner made to communicate wit I.
the other pole. The connections between Tie
wires aud the poles, should be made by meas
CINE that the tube has been introduced into per-
foration made for ITS reception in rock tos
blasted. The tin tube may be secured withinta
rock by the usual method Of ramming in bId
dust or sand, by means Of punch, having bile
for the protection Of the wires Of communicates
already described.
The apparatus beng thus prepared, bya 9.
vanic discharge, produced by the movement d
lever through quarter part Of circle, the f%
wire is gnited. in the place where it ntersss
solely in the circuit, SO as to set fire to the W.
rounding gunpowder. II
AS the enclosure Of the gunpowder in The te
must render it impossible that it should be ,Bc
ed by spark elcited by rammlng, as no mas
Of ignition can lave access TO the charge beSau
the galvanic discharge; and as this can only ga
by design, without an intention to commit ma
der or suicide, Or objectionable neglect. iii
conceivable that an explosion can take place
this method Of blasting, when any person l'@s
uated as to suffer by it.
1t must be obvious that in all cases Of Hastings
der water. the plan Of The tin tube, and Isurf
BY gaIvanic circuit. must be very eligible.
Mr.. shaw is now in Philadelphia, and hope
NAV meet with the patronage which his HSf
merits. ROB'T. HARE
Mr.. James Spicer, OF this city, has invent'; !!
machine by which he proposes to convey the
States mail with astonishing rapldity. IhePi
is simple: cylindrical box, containing the Oh
is to be placed in pipe ten or twelve inches
diameter, Iaid.nnder ground: At each 'sct9' =
the pipe, that is, at the necessary stopping p"
of the mail. air pumps are to be adopted, acu':
exhausters in that part of the pipe anterior 'n
box, and as forcing pumps posterior to u X
which means the box will pass through the
with velocity proportioned to the force snP
ed. -Pouis0n's finer.
C2eaniiness.--Cleanlines is a mark OF P0 n
ness, for no one unadorned with this virtue"
go into COMPANY without giving manifest 0heW