The evening times. [volume] (Washington, D.C.) 1895-1902, 1902-07-05

The use OF a chain for propelling
steamers on the River EIbe was in
augurated in 1856. and has proved an
economical and successful means Of
navigating the Swift current Of that
river. Much Of the region traversed
by the river is sldrted By mountains.
and as the stream is narrow, the current
/ is necessarily rapid and strong The
/ first experiment was made for the pllr-
[ pose OF towing barges under the bridges
with numerous piers at Magdeburs.
Now. chain lies in the channel Of the
river from Melnfck. : point in Bohemia.
to Magdeburg. a distance OF some $50
miles At one time the chain extended
to Hamburg. but as the country is fiat
and the current OF the river sluggish
below Magdeburg, is use between that
city and Hamburg was abandoned n
1888.
Operates Thirty-four Steamers.
The system Is controlled by two com
panies-the Chain EIbe Navigation Com
pany, whose authority extends from
Magdeburg to the Bohemian boundary,
and the Austrian Northwest Steam
Navigation Company. in Bohemia.
These companies own and operate
thiTty-foUT steamers, few OF which
are provided with prOpe1leFs. but most
have no means of loccmotion except
the chain, which they use going up OF
down stream. The dimensions are:
Length over deck. 1853 to 1875 feet;
width amidship, 21-9 10 26-S feet; draft
without feel, 1S to 2.8 feet; number 4
Of boilers, 1 to 2; heating surface. So. /
to S68-T square feet; efficiency OF engines, /
Toe to geo Indicated horsepower
obeys the Helm.
The boats are of symmetrical struc-
ture. and by reversing the engines move
They are provided with rudders- at
either end, operated Independently By a
pilot wheel located in the center Of the
boat
The course Of the steamer IS not
Influenced by the chain, and il usually
obeys the helm as if It were free The
hull and sides are made OF iron, and 10
meet the rise and fall OF the chain, the
deck slopes on al incline Of about q
yard from the center rom each end.
The vessels are provided at each end
with deliverers or outTiggers. which
swing IN = ssmicircle around a pilot BY
means of roller en- rails, and serve TO
take up the chain out of the water at
the bow OF the boat and drop IL at the
stern. The chain runs over the for
ward oUtrigger and over several roller
disks until It reaches a steam drum /
Tor drums) located in the center Of the /
boat, which II encircles three times. /
It is then carried aft OYER another set Of
rollers until it drops into the water
Working of the Chain
by means Of an interposed inter
changeabIe gear. the velocity Of rota-
ton is altered according 10 the course |
OF the vessel up OF down stream
Each OF the chain drums consist Of |
four pulleys arranged flush side by side +
an. stiTened by steel bandages between /
which forged iron ribs are arranged (
Within the grooves this obtained, meas /
ing 80 70 - inches in width and about /
81 inches in depth, runs the chain, OBJ /
tanning sufficient friction for operation /
The driving machinery IN the older types +
OF boats consisted generally OF twin ma +
chimes with injector condensation, but
the newer vessels are fitted with four /
cylinder compound engine with injector +
OF surface condensation. The steam f
pressure varies between 4 and 10 atmos-
pheres- The boilers contain one CT two 1
fame tubes and are provided with re-
turn heating tubes.
The original construction Of drum has
been replaced IN a large number Of
steamers by the chain-gripping wheel /
(patent Ewald Eeilingratn}. This wheel
consists of only one driving drum The
chain which, as above stated, wound
three times around the drum in order 20
insure sufficient friction. in this case
runs over only about one-half of a drum
It is guided over the snip in the same
manner as explained
Turbine PropelleTs in Use.
"On either side of the fanges are
provided fingers. four OF. i've of which
form a hand These fingers are pro-
Eided with springs. which cause the
fingers to press against the individual
links Of the chain. The fingers are also
jCurnaled II. hands which are guided b.
means OF rollers in such a manner that
in ascending. the fingers engage the
chain and prevent slipping of the chain.
At the point where the chain leaves the
drum, the hands and fingers are pushed Il
aside by guide frame, thereby freeing
the chain.
MANY CT the newer type Of vessels
are prev ided with two turbine pro7eIIcrs
OF the Zeurer system, Or ordinary pro
Fellers, which enable the vessel TO run
Gown stream Independent OF the chain.
Auxiliary engines fer slackening or
Tightening the tug ropes. handling TIE
anchor, and operating the tunnel
winches are provided.
The present length OF the chain lying
IL the River EIbe is SIS miles from Mel
nick to SchmiIka bohemian border.
Ond 21S miles from Schmilka to Rogatz
tnear Magdeburg).
How the Vessels Pass.
As there Is only one channel for the
up and down travel, the vessels have to
leave the chain when passing each 9TH I
er N such a case the steamer going
down stream. stops, locates lock link.
and opens it at the downstream end.
To either end of the thus parted chain
ropes are fastened and the vessel slowly
moves down stream until the rope
fastened to the upstream end OF the
chain reaches the drum
Then the rope Is removed and an :
auxiliary chain put in its place which (
IS wound upon the drum--The vessel stu )
proceeding down stream-untiI the chain
reaches the oUtrigger at the bow. At ,
the same time the downstream end of {