New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1907-02-17
TALL BUILDING LIMIT.
Win 1t Reach or Erceed One Hun
dred StorieS?-Why Not?

"Win the projected forty-six story Metropol-
itan Life Insurance Companys tower stand
as the limit OF tall Office buildings?" is
& question business men and persons In
terested in real estate are asking. Not by
a hundred Stories says architect who has
designed many OF Manhattans most modern
sl1yscra pers. I'VE can put them higher and
higher. until the imagination runs out" declares
a consulting engineer who has supervised the
erection Of some Of the taIlest OF our giants IN
building construction,
The building Of skyscrapers these days is
matter of mathematics. There Is no guesswork
as there used to be. Everything that goes into
them Is weighed The size of every steel column
is determined before the foundation Is dug
That is why architects and engineers are able
to say one hundred stories is not the limit OF
height.
There are two and probably three. elements
that have to be considered-the weight OF the
building. the power Of the wind. and. third
the elevator problem This is where mathe-
mates come In
Suppose an order is given TO an architect for
a one hundred story building to be erected on
a plot 100 by 100 feet That would make
structure something like a quarter OF mile in
height; It would mean that the roof would be up
In the neighborhood where the wind is blowing
gale when It IS only zephyr IN the street
II would mean too. that a weight Of several
thousand tons was resting upon a small spot
Of earth II Is up 70 some one to say when the
weight is TOO great, when II rests too heavily
upon one side or the other. and when the build
ing Is so high that the wind viii push It over.
And all this has created a new specially IN en-
cheering.
Ten years ago there no such thing as Il
man whose sole business was 70 design tho
framework Of great buildings: today there are
several Ten years ago the weight Of tall build
ings guessed at; to-day it Is known TO
within a few pounds. Ten years ago The archi-
tect not al all sure that HIS tail building
would not flop over on top OF It's smaller neigh
Dor; but to-day, no matter how high II may
rise in the air. there Is an absolute surety that
It viii stand erect where II Is put
The first thing architect does is to turn his
plans over to the structural engineer and find
out If 1t is possible TO construct from them The
architect does not know. that IS the engineers
problem. And II the building can be erected ne
learns how much space he has 10 divide up into
offices and Railways for the engineer tells him
how thick the walls TO be. how heavy the
supports and where ths great steel pillars are to
b. placed. BY the time the architect gets busy
all that remains for him TO do IS TO lay out the
interior and mako the exterior look handsome
wind Is the only thing that KEEPS buildings
out Of the clouds" said n structural engineer
IF somebody would invent an arrangement for
keeping New York wiudess there would be no
reason whatsoever why two hundred and nifty
and three hundred story buildings could not he
safely erected where twenty-five story ones are
The wind pressure increases In severity
upon the building the higher up It goes and
consequently the strength OF the framework
and the size OF the base much correspondinCly
increase. Here is the onI; limit to height-the
base. II the base were indefinite in size so
also might the building be Indefinite IN height
When the structural engineer has found out
how hard the wind pressure on the building will
be nc determines the strength Of the steel
frame Then when that is nnlshed-on ma ner
that is-hc weighs IT. Every bolt and bar and
beam is put down and summed up Then he
figures up the live weight-so many pounds Of
desks, 50 many tons OF flooring so many tons
OF human beings, and 50 many pounds Of books,
And. presto. he knows how heavy the sky-
scraper will be before a shovel touches the
earth.
His next step is TO find out If the earth viii
hold the load. That means borings dfty and
sixty feet deep, so that tho kind Of rock may
tall buildings, for the bed rock is granite
the Samson among rocks, and there Is no lnit
TO the amount or weight it can carry But
there are parts Of New York where the he'd rock
is too far down to be uncovered and the build
ing must, as a consequence, rest upon hard pan
or a yet softer bottom But there are only small
strips or this soft stuff; and besides, New York
hard pan is as tough as sin. The BROOKLYN
Bridge piers rest upon it. so does the Post Ofics
and there has been no sign OF sinking yet.
so, with the nature of the foundation deter
mined and the weight known. the engineer gives
his verdict But If 1t is affirmative his work is
not over Yet. He has TO then iurgle Nth
weights. The whole body Of skyscraper rests
upon about a dozen pillars. covering not 1 per
cent Of the total ground area This has to be
divided up so that every inch Of the bottom will
get its just proportion Of weight, and no sec
=