The Saint Paul globe. (St. Paul, Minn.) 1896-1905, 1902-08-24
SkyScrapeTs VIII
Be Short Libed.

HAT is the probable lifetime
IvW.YI Of the skyscraper?
NA That depends entirely upon
+" its genesis.
Skyscrapers have been
built, under certain faulty
conditions, which may not outlast half
century; there are others which compe-
tent engineers believe likely to survive
threescore years and ten; still others
may prove centenarians. Time alone can
tell 1T
Just before Mr.. Andrew Carnegie last
went abroad he led a Pittsburg friend to
Madson-square and confronted him with
the huge wedge-shaped structure, which
like a colossal ship thrusts it's white
nose into the junction Of Broadway,
Twenty-third-st. and Fifth-ave.
Its daisy" said Mr. Carnegies
friend.
"A mountain daisy" said Mr.. Carnegie.
That, at least. is one of the stories
heard by a correspondent while convers-
ing shop with an eminent consulting civil
engineer The talk was about the
longevity of the up-to-dato, up-to-the-
sky steel structures now building or built
in New York City.
How long will they stanG?" said the
engineer. ''Who can say? In an earth
quake probably about as long as the seis-
mic shock itself They'd all come down
like pack Of cards. But under normal
conditions the age Of the skyscraper is
the age Of an old maid-we can only guess
at 1t. We must wait until one of them
Dies
It was pointed out that the lifetime Of
brick and granite, Of the Chinese wall
and the pyramids was not at all prob
lematical
'tBut that's different thing entirely
What are they but foundations anyhow?
And bear in mind that in this climate
there is no building stone which is i'm
periShable. The question is simply this
Will the inner steel structure of the sky
scraper last as long a solid building
of granite or Kavlin brick? The question
was brought to issue by Gen. William
Spoy Smith at a recent banquet Of real
estate men in Chicago. The general is a
West Pointer and a thoroughly compe-
tent authority in engineering matters. He
has disclaimed any intention of posing as
a prophet of evil, or Of being regarded
as an alarmist in the profession. But he
did and does declare point blank that a
great danger of insta bility and early de-
cay exists in the careless or ignorant
manner of erecting many of our finest
examples of tall office or apartment build
ings. There is always. of course, a serious
menace in the weather to improperly pro-
tected steel"
The writer saw Edward L. Abbott
about the matter. Mr.. Abbott an asso-
ciated member of the American Society
of Civil Engineer, has an Office with Mr.
Charles Sooysmith, son of the general
(who divides his name in two), and he
discussed the skyscraper's chances OF life
with air of dispassionate conviction.
Il think" said he, that / can put the
matter in a nutshell. 1t Is this way:
CHI
strain per unit of section of one-fourth
or one-ffth of the ultimate strength of
the steel used in building; that depends
upon a given factory. Say that is five It
means that at every point the structure
is built to sustain five times the strain
to which it is actually subjected; and 1t
Is rule of construction that no building
should be weighted beyond one-haIf Of it's
elastic limit. Now, suppose the founda-
ton of a huge twenty-story steel struc-
ture is slowly but surely weakened by
ccrrosion, what results? What must re-
suit? Why it's decay at the roots Of
course, but not Of necessity It's instant
collape. 1t must go into repair. That's
about what Gen. Soodysmith said about it.
1.-THE simple fact is that while too little
care and precaution actually, are, too
much cannot be taken with the steel
which forms the skeleton Of the sky
seraper. We engineers are less interested
than the architects in it's skin and COM
pleXion. The parts exposed must De
sound. Steel comes from the mill in a
more or less dirty condition. Every inch
Of the foundation steel should be careful
ly gone over and the scales and dirt re-
moved with steel brushes, and it should
then be washed with an alkal in order to
remove the inevitable oil and CRIME Then
comes the most important detail in tho
process Of erection.
well, should like very much TO have
peep forty years from now at the steel
which forms the foundation Of some OF
our biggest buildings
Though majority Of the city's consult
ing engineers visited by the writer agreed
in the main with Mr.. Abbott's views. a
few were disposed to treat the matter
lightly.