Milford chronicle., 1908-01-03
THE WIND ALOFT.
Towering sl<yserapers Have to stano
lot of Blowing.

L-OL
Tho wind velocity in the vicinity Oh
Novv York is not on the average the
,,oor round extraordinary. but at times
Il blows at the rate of fifty and sixty
niles an hour. Then signs go scurry-
inc np Broadway, umbrellas turn IN
side out. and the wearers OF skirls
s+rpoqle frantically to hold toselner
tboi, various articles of clothing. Inc
man on the top of n skyscraper Is llAe
sailor sent aloft in storm 10 IutI
sails. He clngs by tooth ana nan ~
whatever support he can fnd anu ge'S
/ down again. if he can, with more oiDC
ri+v than he went up. This Wlhu We
locitv-not in its average, nut At 10
,,,avimum-is an important matheHlat-
tool nroblem with the engineer Wnen
be rms a building twenty 10 lor'y
stories high. The wind pressure Oh
+o1l building must be reckoneu very
carefully. A structure five or SIN nun
drod feet in the air must be Draeeu u
-,.i+Istopd wind pressure OF some
fling like thirty pounds to tne squai4 eaat
foot With a tower slXty-hVe
souare and several hundred rect aoote
= +bo ton of the main building there Is
b = 1,,ind Dressure at certain seasons VI
5 +be wear sufficient to drive uoAen
ocoan steamers half across the ocean
IL If could be harnessed and conVerteu
y into available horsepower. Ine
sistonce TO this wind pressure must "
:. secured by angle braces every secon1
or third story ond the whole calcuiaIeu
kIsao1 formulas.
5s If there is any doubt in the mlLu ~, y,
- the skeptical about the force ot u,
= wind at great attitudes, ne snoui'
- dron q nlumb line from the top OF tn'
s+r,cture to the bottom of some III
:, glosad court on a windy day. Inc I'LL
" ,,o,,Id then be found to vibrate AM
{, swing very much like the pendulum o
II olocl, 4 recent test of the viDrauo
,, ~ tall building in heavy wind wa
fms made. and it was found thal III
limo SWING back and forth through
arc Of nearly two degrees. Nature ha
"a, s,,nplipd us with something that corr
o1d sponds to a plumb line. Our DIali
-, snpear to float in a liquid when stan
- INC on vibrating tower, and the uiA'
=. sensation communicated to us IS II
oil fancy The rocking Of tower u
lns or six hundred feet in the air Is Il
uu 5 verv different from that of snip IN
~ sen, There are cases Of "seaslc
~ - ness among the cliff dwellers OF Ma
,nr - haitian. and they have to get acc'
i0' toned. to their high attitudes Delc
they are immune.
If the wind pressure should at i"
time reach the maximum stress
,o1var for the Singer building. II wo'
'0'' ranresent over its whole surface
-, force equal to 12s,OOO foot tons. AS
0etn total weight of the tower is only 25''
" TONS. It would he possible to oVert'
luel this norton Of the building, or, ratI
g,- pg,- uft 1t UP from its foundations, sno
-nu the wind blow at such velocity as
1910 exert an even pressure of thirty poul
nor SQUARE foot To avoid any 81
IN contingency each heavy iron column
AlUei anchored to the foundation calss
scOF. come sixty feet below the SURFACE
n Oh the ground. The margin Of safety I
sne obtained is sufficient to Withstand
nno of the summer wind squalls OF
srlel ends Of West Indian hurricanes WI
sweep across Manhattan. - Harp
- Weekly.