Bristol news. [volume] (Bristol, Va. & Tenn.) 1867-189?, 1870-01-14
IN THE DEPTHS.
HOW col. EAGS Is BRIDGING THE
MISSISSIPPI AT ST. LOUISA
TRIUMPH OF SCIENCE.

HOW col. EADS Is BRIDGING THE
MISSISSIPPI AT ST. LOUISA
TRIUMPH OF SCIENCE.
A reporter Of tho St. Louis Democrat
gives the following graphic description o
how lionel Il ads Is sinking the great iron
csissons Tor the piers to the bridge across
the Mississippi ut that city; 'avn
Two immense piers are To be constructed
in the river, OF solid stone masonry. These
piers to be substantial, must rest On the
solid rock that lies fifty, sixty or a hundred
feet under the ssud, under the water OF the
rushing rrv r. The question was, how tu
get down I'll Theses feet through water and
sand, to hnd the rock to lay the solid fGun-
dstiOu. One way would have been to build
Golfer dams, aud pump out the water, d &
out the sand, aud lay the piers in tue empty
space. But this was imprscticabIe, II not
impossible, and Mr.. Esis' science aud VIZ
dom selected another plan, which, though
not original with him, has been greatly i'm
p owed OF by him, aud applied more sens
by aud effectively than It wasever done be.
fore. Thi. plan vas to build within Gals
s)n, till the rock was reached aud the pi,r
conf leted, AID to make this compreheusi
ble TO every child il shall DO illustrated very
simply.
ILLUsrRI r',S OF THE SINKING cAIssoE.
Did you over hold a goblet bottom side
up, and press IL dow Into a vessel Of water
IL YOU have you know the water does not
enter into the empty tumbler, but the air 10
II keeps The water out, and as you sink 1t
aud press il do~n il drives tho up the SIDES
Of tho vessel. Now suppose instead OF Tho
goblet You hold an inverted metallic vessel
IN the saIus way, ,ha same facts would be
true AS long ~ the air was In the inside OF
it, II the bottom of this Inverted vessel
were at, you could put brick on it., AMI
atothsr, and anoths' until you have weigh
ed enuu Ih to sink l. to tue bJttOm OF the
water, Nhen you have pier Of bricks
Nov this Is exactly what Culouel Eads has
dOns in huildi the east' IN per Of the
bridge. But lis Inverted "pau is Of the
sizs he wishes To, b it.,ti, If the pier TO be,
aud is forty, dfty, sky feet across, as the
case may he. o, coursr this INN II
"iron DISH" bottom side up, was held IN
position On tho water hy mscb'uery. lie
then laid solid course of s'oIe masonry on
the " dish" or C tisson, T" and as he bu 1t.
| the weight pressed IL dogn into the river,
| aud now il hos rescued the bO. tom of The
river, aud even feet Into tho sand, aud
the pier is forty or fifty feet high. But IL
has yet u Sink MY OF sixty feet iurt O. to
meet sold rock, aud the sand cannot he
displaced as tho water wns, but must be re
lnosei by artii iai means, aud this is What
| is being successfully done n w. Or cou' SO,
AZ the sand is dug away from und'r tho
| sides q the caisson Il " II sink just as fast.
| To d this AWAY men must get into the
! 'upiurn, d dish" or ".aissnT,' or air
| chsuiber" IN Ter the pier AID work there.
VISA. x lain how this Is done.
ENTERING IHr AIR cuANB.R.
Egeryone will understand that the ar
| In tue chsmber must be very much cJu-
deus. 4, and that a most essential requisite
is that 1t must be kept s., ami To- allowed
TO escape. II direct opining we're made
TO IL anywhere, the the escape OF air would
cause the water aud sand 10 wash IN from
underneath, the vacuum would bs instantly
filed, AID here Nuald be the tul Of sink
ing the cassDn aud the pier. Col Eais has
arranged = very simple aud perfect way d
entering this chamber, which is now six or
eight feet lower than the bottom Of the
liver, and Yesterday We vent down into u
and saw the men a. work. 10 the center
| Of the bier he l,is circular vel nicely
-, finished with hrick sides, and six or Ugh
feet across. This we'll reaches To the very
, bottom, is now fitty feet deep, and Il gh
of steps built circling, next 10 the wall
from top to bottom. Down these steps WI
r went together TO the bottom OF the WE'LL
4 There we fOuDd door Of an OVAL shape
' and about two feet In diameter. L'okinl
I, IN NJ. Jaw a room about six feet high, deel
! and and wide . soIt OF eel Aud dam
"oven." "CraNl in aud I'll follow, sal
Colonel EAds. la We won't through th
oval hcll, knocking of q hat, and slight
; humping a head. Co.onel E.ds camo, also
y | with q pine stick and lighted candle stuc
: | on il, or we shoul have been Ia Esypiia
darkness. The Colonel closed the it'll
. iron door by which We had entered, and
u shut us in 'iair tight" He then poiutsd
another similar door right opposite, 40
said "That opens directly into the ali
Is chamber under the whole pier. l will IL
o the compressed air in here gradually, az
!, When the equilibrium Is established ina
4 DIOR will open OF itslf, aud We will 90
At through g." S0sAying he turaed the fauc'
"a of a brass atop cock, tho air from the ali
II chamber came singing through II like ates
I, from boiler valve, the sTAnE sensalio
/ crept over us.
a What II something should burst dow
~ here What power could open tbs doc
m behind us, now being held by the glal
pressure Of the compressed air Suppo'
iainting came oV one, aud this roarin
ringing, laundering In the ears ahomi Ia
for life But in Just one minute ana hs
is the rush of air ceased, the olleF door oge
ed, the ears were all right, and with u
pleasant sensation we were me oond ID
w. ed atmosphere, and crawling through IL
IL door stepped u. on tho sand lh'o 'ho a.
% chamber. Ten or d, zvn mrp ~ele Ia
80 at work, oseh with a cAnile, the huge ea
en- son vas az AROUND Us, gustening with wat
no drops and from rust in Olnuon, aud the u
! - iron roof vas overhead, with ali its tons
a, sioua aud pier above Us Tue sAal
~ damp, bat not wet, rs tho compressor
~ NJ, sphere druve,all the wat'r o ~ throa
w the sand aud up through tho sand and
90 throngh tho water, which No had vbssrV
w b, fore we came down, TO DO 6nobing
w around thepieri like Champagne m gla
y. wHAT We FoUSD USpsR ruE PIER
o9 We walked all about tho alr'chamt
90 from ct TO end, aud silc to ttie' ana 81
Ol how the sand is reunited, aud how tho
20 Is supplied for tho inmates u i've on
% Powerful air pumps, worked by st"sp
80 heat, uDon the surface Of tho river, toT
~ water down tubss that are run through
~ stone work OF the pier, and Trey Keep p'
1911 thn atmos Dhere. No leFs ihin seven pu
100 erful sand dumps are also seen Win IN
vi feet pruieeting do yn to the bottom,
$40 lshtiDg II up through the p'pes, ana tni'
vi inc IL oat above the var. zee OF I'M
SEA numps will take this SAND away az last
80 workmen eau lay tho siVIo york on
1888 pier, sn In 4 hours the pump We saw
la work took out 81 cubic fsot In al minul
Ia or ono hundred carloads 10 about
40 hours. But bow can pump thro"
a79 sand : some ono asks. just as silly aS
l45 were before We saw IL. A temporary v
les or hox, is put under the foot u put
mr. and a large hose brings down water iron
nj forcs pump above. This hose opens 10
"a. box, the water IL sucked up tho sand pvl
n,r aud two OF three men shovel sand into
box TO miugle with the water aud DO thr'
ava out with it-aDd that Is how the sand put
ot xorkl Their success has boon inlly
600 ted-lhe work is going on sAiisfsetoril
"a and, n good luck happens, Col. Ids
hs, Hnd his q st great pier resting on the .