e brake is released.
A light spiral spring is placed on each of the screws, in order to free
the brake from the rope the moment the pressure is released. The hand
rope has a turn and a half round the pulley, and this obviates the need
of holding both ends of it, and thus leaves one hand free to guide the
descending weight, or to hold the rope of the pulley blocks.
_Engineering_ says these brakes are very useful in raising heavy
weights, as the lift can be secured at each pull, allowing the men to
move hands for another pull, and as they are made very light they do not
cause any inconvenience in moving or carrying the blocks about.
Manufactured by Andrew Bell & Co., Manchester.
* * * * *
WIRE ROPE TOWAGE.
We have from time to time given accounts in this journal of the system
of towage by hauling on a submerged wire rope, first experimented upon
by Baron O. De Mesnil and Mr. Max Eyth. On the river Rhine the system
has been for many years in successful operation; it has also been used
for several years on the Erie Canal in this State. We publish from
_Engineering_ a view of one of the wire rope tug boats of the latest
pattern adopted for use on the Rhine.
The Cologne Central Towing Company (Central Actien-Gesellschaft fuer
Tauerei und Schleppschifffahrt), by whom the wire rope towage on the
Rhine is now carried on, was formed in 1876, by an amalgamation of the
Ruehrorter und Mulheimer Dampfschleppshifffahrt Gesellschaft and the
Central Actien-Gesellschaft fur Tauerei, and in 1877 it owned eight wire
rope tugs (which it still owns) and seventeen paddle tugs. The company
so arranges its work that the wire rope tugs do the haulage up the rapid
portion of the Rhine, from Bonn to Bingen, while the paddle tugs are
employed on the quieter portion of the river extending from Rotterdam to
Bonn, and from Bingen to Mannheim.
[Illustration: ROPE PULLEY FRICTION BRAKE.]
The leading dimensions of the eight wire rope tugs now worked by the
company are as follows:
Tugs No. I. to Tugs No. V. to
IV. VIII.
Meters. ft. in. Meters. ft. in.
Length between
perpendiculars 39 = 126 0 42 = 137 10
Length over all 42.75 = 140 3 45.75 = 150 1
Extreme breadth 7.2 = 28 8 7.5 = 24 5
Height of sides 2.3
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