The morning call. [volume] (San Francisco [Calif.]) 1878-1895, 1892-07-10
A SCIENTIFIC EXPLANATION
Why Windows in Some city Buildings Wer.
Shattered and Others Escdoed

fhy Windows IN Some city Buildings Wers
Shattered and Others Escaped
What struck people as most peculiar In
the effects OF the explosion on buildings in
the city was that in the exposed portions
upper windows were shattered, while In
the business portion. such as KearnY, Post,
Geary and other streets, the effect on the
glass was in the lower parts Of the build
ings.
With the view Of obtaining scientific
explanation OF this popularity represen-
tatve of THE CALL called at the Weather
Bureau in the Phelan building, but as Lieu
tenant John 7. Finley was confined to his
apartments in the Hotel PIeasantOn through
sickness, the reporter was advised TO call
upon him.
Lieutenant Finley was found In bed. but
courte0usly gave all the information he
could.
THE conditions" said he, "are very
similar to those when the tremendous vol
canic eruption took place at Krakatoa Just
south OF the equator, near Sumatra. At the
time of that explosion it was supposed that
the gas and lava were thrown distance OF
from 80 to 90 miles in the air. That caused
huge vacuum fully 10 the extent of tie
whole island. The air rushed ia from all
sides and filed this vacuum, resulting In a
violent conclusion on all objects within
that radius. The action of the air is equi-
valent TO the shock of a cannon-bIll. 1t is
somewhat similar in the case of q tornado.
Its cloud diameter Is about so rods, or u
quarter of q mile, and the depression of tne
barometer within the tornado cloud is es-
tlmated 10 be within two or three inches,
something enormous. That would give
velocity OF over 1000 miles an hour. which
is ineonceivabe although mathematicans
have estimated the velocity st even 1000
miles an hour. This creates an approach
to vacuum, as there scientifically can be
no vacuum i'll the air, When, therefore,
tornado passes over or near to buildings
the air rushing in from the sides has suf1i-
Client force to explode the buildings, In
stantly throwing the roofs into the air aud
the sides fall outward. The air being sud-
denly taken away from about the building.
the air within the building has force of
10 pounds to the square inch, and you can
readily see the tremendous effect of the
pressure of the atmosphere.
THE air currents are modified by the
topography and other cireums tances, and the
effect can only be determined by examining
all the conditions of the surrounding build
lngs. their structure, openings, etc. There
is an elastic medium, the atmosphere and
its vigor depends upon the air in the build
ingS. The air n all these shattered build
ings is all rushing toward the uprush caused
by the explosion, then the air OH All sides
rusheS toward them.
when many people see a tornado coming
they close their doors and windows. That
| Is precisely what they should not do. We
| often hear of one building being completely
carried away; of the portion of another
b, lug carried away. That is explained by
the fact that in he former all eeress of the
air in the building was shut off. and in the
other the portion not demolished had the
doors and windows open and the other p0r-
ton had them closed.
'The Kratatoa explosion made seven dis
tinet pulsatiOns in the atmosphere round
the circlo Of the globe before it qaieted
down."