The Washington herald., 1909-03-21

the Capital City will for a long time. at
least, escape the advent OF the sky
scraper. Congress and the Commission
ers have placed a ban upon buildings
more than ten stories high. as yet land
values and public sentiment favor some
limit to the height Of buildings.
In New York and other cities. however.
where land is a hundred times more val
liable than here, no such restrictions
have been put upon the erection of tall
structures, and the slxyscrapers of Man
haitian Island are among the construction
wonders OF the world.
Contrary TO public opinion the use OF
iron in Strengthening and stInening build
ings is not a new element in construction.
says the New York Sun.
AS a matter Of fact il is centuries old.
Iron clamps were used by the Athenians
IN binding together the massive stone
blocks Of the Parthenon. Iron even was
used in the construction Of the obelisks
and other structures of antiquity
Due 10 American Builders.
But TO American engineers and builders
IS due the credit for the development Of
the modern skyscraper The introduc-
ton Of bessemer steel made the erection
OF lofty buildings physically possible
The growth OF the traction elevator and
the establishment OF organized methods
Of construction made their erection prac-
teal as well as profitable. The develop
ment OF Manhattan has now made TWEEN
y. thirty. and forty story buildings an
economic necessity.
The high price of real estate and the
restricted area Of desirable sites at the
lower end Of Manhattan Island have
served 10 bring about the erection Of
group Of buildings without an equal in
any other city in the world Below
Chambers street land Is worth from $50
10 $500 a square foot. Exceptional plots
will bring an even greater price. The
southeast corner OF Broadway and Wall
street, considered to be the most valuable
site in the city, sold not long ago for
10000. This Is at the rate OF $500 a
square foot. the highest price paid for
real estate in any city in the world.
Land More Costly Than Building.
1t is not at all unusual for the cost Of
the site OF a new building in this city to
exceed the cost Of the structure itself
This was the case with well-known
landmark al Twenty-third street. Fifth
avenue, and Broadway, where the land
required for the building cost s.. .50O. COO.
Where such vast sums are paid for the
building site II becomes necessary. TO pile
story upon story until the area OF rent
able floor space Is sufficient TO guaran-
tee a reasonable profit on the cost OF the
site and the building over and above
taxes and carrying charges
Although the first extensive use Of steel
In building construction stands 10 the
credit Of an English engineer the princi-
PIE has been developed In this country 10
point never dreamed of at its inception
and not yet attempted abroad. In the
early stages OF building the old idea OF
having the external walls made heavy
enough TO carry the floors and floor loads
still was adhered 70. the only change be
ing the substitution Of wrought iron for
wooden floor and roof beams In 1883
the modern system OF having the steel
framework support practically all the
weight was inaugurated The first struc-
ture TO be built under the new system was
the Home Insurance Building in Chicago
II was only ten stories high Since then
the height OF skyscrapers has been rapid
" rising 70 twenty. thirty. forty. and even
fifty stories. A sixty story building has
EVEN been seriously considered.
Limit OF Ordinary Buildings.
The limit Of height for an ordinary
brick or stone building without a steel
skeleton is reached when the lower walls
become so thick as seriously to encroach
upon the usable floor space Of the build
ing The tallest structures of this kind
have stopped at a height Of thirteen or
fourteen stories. The walls Of the ground
floor of a fourteen story building of the
old type are nearly three feet in thick
ness. The introduction Of steel columns,
girders, and stringers in Il building made
Il possible to transform the weight Of
each story 10 the vertical columns di-
rectly below t.
The outside walls were thus divided
into sections corresponding in number 20
the number Of stories IN the building.
Each section Of wall is upheld by steel
crossbeams which transfer the weight to
vertical columns set one upon the other.
the bottom column resting upon mason
~ foundations that extend down 10 bed
rock. The intermediate spaces between
columns in a building Of steel skeleton
construction require only a thickness of
wall sufficient to serve the purpose Of
inclosure.
Steel Adjusts Load.
The Introduction OF steel serves not
only to reduce the thickness and coinci-
IDENTIFY the weight of outside walls but
also makes it possible to have the loads
concentrated upon a specified number Of
vertical members whose supporting power
has been accurately determined. This
means a corresponding increase in the
elements Of safety and durability. The
stresses in a tail building can be calcu-
lated to a nicely. and by introducing the
proper amount OF wind bracing Il may be
made absolutely secure against overthrow
by storm and reasonably secure against
earthquakes
Furthermore the steel skeleton build
ing is a form Of construction that lends
Itself admirably to freproofng. If the
columns and beams be thoroughly pro
tected by terra Gotta or concrete ana
metal or ireproofed wood be used for
the construction Of doors window sashes.
and frames and so far as possible for the
furniture fire among the contents Of one
Office will be localized for want Of com
bustible material 70 seize upon In the
building itself The San Francisco fire
proved that a modern Office building OF
fireproof construction could go through a
fierce conhagration and yet remain so FAR
intact as to be capable Of speedy repair.
Life of an Office Building.
The length Of life Of a modern Office
building Is a mooted question. The con-
sensus seems to favor an existence Of sew
eral thousand years. The structural steel
used in its makeup. however. still is an
~untried material. It's ability to withstand
stress Of weather has not been determined
definitely. What slight evidence has been
collected would seem 20 favor az almost
perpetual lease OF life, provided ordinary
safeguards are observed in method and
thOroughness Of construction