Wilmington journal. [volume] (Wilmington, N.C.) 1844-1895, 1855-02-02
and left in an unfinished state By

Camden Branch to Cane Savanna Road the 18th Nov
coincidence carried the first train through the Road on the
10th October, 1854.
In professional point of view the construction of the Road
serious obstacle in the character OF
foundations encountered in the passage of Of the
Your attention was directed, in Report of January
2b $780, to the passage the Pee Dee River which
then regarded first in Importance and work of
ordinary magnitude The superficial examination of the
foundation only had made that tme
produce conviction that it of the most formida
BILE streams the great chain Railroads between
the North and South The foundation then regarded
loose floating sand, but not extending to SO great
in which of the many plans of Golfer dams could be
Among the many plans suggested, my attention was
rec to the pneumatic of driving piles in tebru
Esq present able Chief Engineer of the Baltimore
Works who then interested in the patent right
and to whom in October $780, expressed the opinion that
would not hesitate to recommend this process upon an
examination of the bed of the river 1.-the sand should ex
tend depth of twenty or thirty feet"
In July 1851 with ordinary auger, number of holes
bored the bed of the river to depth of nine feet
within which distance sand only was encountered In com
muncatng Major Gwynn copy of the profile with the
result of these examinations expressed the opinion
the best plan for putting in the foundations of the piers
will be by the OF Dr. Potts Pneumatic casron Piles
filed with concrete
The plan subsequently adopted by the Board upon
the Recommendation of Major Gwynn and it purpose
explain of the results which obtained and
to describe particularly the Improvement and discoveries
which, conceive, made during the progress of the
In the Report of Major Gwynn, made at the last
annual meeting the od"s operandt is very accurately de
cbed, but the difference between the plan and principle
upon which it commenced. and which it was fin
ished not clearly defined The Pneumatic Process
upon which the work commenced consists in creating
within the cylinder which the water sand
&C. to rush and in its carry with the material
from the bottom of the tube, causing to descend by its
own weight The is first created in chamber,
which is placed in communication with the cylinder by
ordinary suction hose and closed opened by valve
projection attached to the chamber The power,
relative cubical contents of the vacuum chamber
portion the cylinder above the surface of the water and
the perfection of the In the operation at the Pee
Dee the chamber consisted of two sections of cyn
der Is feet in length and generally the cylinder pile 10
feet above the water line therefore the power ydrostac
and pneumatc only 8l8 of the vacuum obtained in the
chamber which usually about equivalent 26 inches of
perfect vacuum being 81 inches The effective
power therefore, that due to ii lois inches of mercury
or shout s 2l0 fbs per square inch -,
about feet below the bed of the river about feet in
diameter This for time arrested the progress of the
perfect state) could be completed.
The Air Lock, it is usually called is not strictly part
Trigger sinking shaft through bed quicksand coal
mine and accurately described in the supplement to Ures
plan of Lock- similar to that used the Pee Dee river
well described in the read before the of Civ
c method adopted in constructing the foundations Of the
bridge the Midway at Rochester, and from which
encountered in sinking the cylinders the paper states 1t
therefore, decided that the Pneumatic should be
e the cVeda e p ia
ter and feet in length had wrought iron securely
in plain, with sectional of about square feet appro
prately called Air Locks projecting feet inches
the 6P he eS M feet below h
lar opening feet in diameter with Flap working hor
lzonta hinge and an iron door feet by feet inches with
furnished with two sets of cocks the for forming
muncaton between the cylinders and the chamber and the
other between the chamber and atmosphere. IT
Earl in July the Air Lock completed and every thing
in readiness to the sand above the tree and cut
away AT first 1t extremely difficult to induce the OPP
eatves employed the work enter the Lock- while the
condensed air escaping from imperfect joints much
| Ikp aOfc 1aok Roilar
ton to this during the of equang the change of
pressure the tympanum of the for time
ceedngy painful and in instances produced hemor
rhage from the lungs Owners of hands, and indeed of
the principal operatives believed that the nhang
of the air deprived Of the Oxygen necessary sup
port te and generated Cab5nic Acid Cas- which exceed
deerous to animal fe and would eventually produce
serious consequences Although we'll ascertaned that
this which is thrown from the lungs each respiration
much heavier than common air. yet the laws which
its elasticity under various well
fined while present. ore closely observed the appear
of the light which by peculiar halo around its top al
ways indicates the of this Cas- when sufficient
quantity to njure animal life.
No serious difficulty in removing the sand
or In cutting the tree which arrested the descent the
Cylinder and which proved large Cypress perfectly
sound AS soon as the tree cut and the compressed
air discharged The Cylinder settled down fee-and
freshet coming about the time Operations
pended The second Cylinder lowered its place
was driven to depth of about six feet this DEPTH the
friction counerbaanced the exerted by the
ana 1t necessary to the interior col
umn OF sand Efforts were made to pump out the water
and remove the sand but it found that the water
could not be reduced by Pumps more than six feet
below the level the outside the Air Lock again
used and at the expiration of the first days work hen about
feet Of the sand had been remove and the operations
suspended the Cylinder observed settle several
inches On the succeeding day the removal of the sand the
bottom of the Cylinder completed and, with view of OBJ
serving the effect stationed at each valve with d
recon at given signal to open it, that the compressed air
might be suddenly discharged The result was that the Cyn-
der driven six feet which exceeded the greatest effect
duced by the exhaust nrefectng upon the
which produced this effect discovered that it the hydros
atic action of the which
meath the bottom of the cylinder which partially relieved
friction and caused 1t to descend by its gravity In add
ton to this after the air in the cylinder had become
ed until equal the force exertcd by the the
outside the pressure could be increased and the
air which pumped by the continued action of the
escaped under the bottom of the cylinder and become ncopo
rated with the Sandstone of it rising to the surface When
the compressed discharged, the equilibrium de-
royed and the air. in rising to the surface the outside and
around the cylinder still farther relieved friction (This
the second cylinder also encountered its descent oak
ABOUT feet IN diameter butt unlike the first it soft
that the weight of the cylinder easily through it, On
posure to the atmosphere became hard
was perfect Ignite This is mentioned to show the different
results produced on the two qualities of timber by the
OF water they the evidently
posted at and belong to, the same period of tme.)
1t therefore, apparent that the hydrostatc action
water more effective than the pneumatic process
was subsequently, used Principally in driving the remaining
These striking results, obtained individual
been reproduced working SCALE with many persons
once enclosed in mining shaft encased with tubing
formed of series of large sheet iron cylinders rveed
gther and sunk great depth through the bed of the
river Loire near Lauguire
The of coal in this district of France lie under
stratum of quicksand from Is 20 thick GO ~
YARDS and they had been found be inaccessible the
ordinary modes OF mining previously pracced The obsa-
Gle had been regarded be perfectly
that every portion of the coabasn that extends
THESE auVal deposits though well known for centuries had
remained untouched To endeayor by the usual workings
to penetrate through these sem-fud quicksands which
communicate with the waters of the Loire was in fact
choFti 0fr.xvo