Wood County reporter. [volume] (Grand Rapids [i.e. Wisconsin Rapids], Wis.) 1857-1923, 1892-12-01

Dep0slting helm as Gently as
Mother Lays Her Babe
To Hest.

have WONDERED III vain how they reach
Ell their pace, the problem OF moving
and lifting vast weights has occupied
mechanical minds.
The product OF theSe studies is the
travelling crane, Il monster claw, SuS-
pended at variable heights, that can,
at the viii of the hand that guides the
lever, transfer through space great
pieces Of ironWork, sometimes reaching
the weight OF one hundred tons, and
deposit it as gently as the fall of Il
feather on the exact spot designated
Although the travelling crane existed
Ill Europe d quarter of d century ago,
1t failed to attain perfection in motion.
The speed was too slow and it obtain
ed but little foothold as a labor-saver.
The American machinistS attempted
the task of increasing the speed. The
result has been a crane with the aver
age speed Of from one to two hundred
feet per minute
The first cranes used in this country
were. propelled by hand. Steam and
electricity have supplanted this mode
Of propulsion and it was through them
that the present high speed was attain
ed
The progress of crane building i'll
this country for a long time was very
slow, and the first machines introduced
were abandoned through lack of use.
now, however, and are universally used
by large concerns.
1t took ten years for the travelling
crane to become appreciated. Their
general use has led to another develop
ment, that of the swing crane, which
travels back and forth and swings
within a given radius. In 1886 th2
first travelling crane manufactured in
Philadelphia was produced by William
Sellers q Co. 1t was rejected after
short term Of service us being too slow.
They later manufactured a crane that
ran siXty-siX feet per minute, and by
alteration and improvement have sue
ceeded in increasing the spe d to two
hundred feet This is regarded as the
highest standard speed.
A crane travelling at this rate is in
daily use at the Southwark Foundry
in Philadelphia. The Baldwin Loco
motive Works had built by the same
company a crane that is capable of
lifting one of their heaviest engines,
some of which weigh nearly 100 tons.
fifteen or twenty feet from the ground
and carry it at a high speed clear
across the erecting shop, a distance of
nearly 100 yards. 1t is propelled by
electricity and it's motion is governed
by one man. who needs to exert no
force beyond a gentle pull on the lever.
These achievements have gained for
the company the name of the pioneers
in the manufacture of high speed
cranes. 1t and three other constructors
of lifting machinery will each furnish
crane to be used in Machinery Hall
at the Columbian Exposition for con-
veying passengers the length and
breadth of that great structure. The
machine the Sellers Company will fur
niSh is to have a lifting capacity of
twenty tons and will be capable Of at
tanning a speed of five hundred feet
per minute. The motive power will be
electricity applied through two ten-tOn
! trolleys and it will have a Seyenty-siX
feet span. A huge cage will be sus-
pended from the centre with a seating
capacity for nearly 200 people The
runaway will be 1,400 feet long and
will be traversed in less than three min
utes in absolute safety.
At the Paris Exposition similar
crane was constructed, except that in
stead of Il suspended cage it was pro-
videG with a platform on top, on which
were ranged rows of seats. 1t was
viewed as a wonderful achievement in
the art of mechanics. Those to be con-
structed at Chicago promise to far
eclipse the foreign production.
An order has been placed by the gov
eminent for three cranes, one of which
is to be used in the Brooklyn Navy
Yard, designed for use on the dry
docks. 1t is of the swinging travelling
type, with a lifting capacity of 40 tons.
With this weight it can attain speed
of 200 feet per minute and a swinging
radius of Sc feet With a Bottom weight
the radius can be increased to 10 feet.
The crane is run on swiveling trucks
of 16 wheels each, along track laid
around the edge Of the dry docks. 1t
can run around a curve as easily as on
a straight track and attain the maxi
mum speed. The motors, which will
furnish both the motive and lifting
power, are all on the crane, so that this
vast machine is entirely independent Of
any outside force.
A successful test was made few
days ago and showed this extraordinary
piece of machinery to be capable of
doing all that was claimed for it. This
is the first of three similar machines
to be furnished the government by the
same company One other will be also
used at the Brooklyn Navy Yard, while
the third will be placed in the Norfolk
Yard. These are the first cranes of
this type that have been put on the
market. and they mark new develop
ment in an already gigantic industry.
To construct a large crane properly
a score of men work from four to five
months. 1t is absolutely necessary to |
use fawlesS metal The forgings are |
made with the greatest care and the |
least deviation in measurement causes |
them to be rejected In price they /
range from So. 500 for the small ones |
used in light work to $4,000, which |
represents the value of the 1OO-ton |
giants.