December, 
19 21 
31 
THE BAROMETER IN THE HOUSE 
Not Only Does the Barometer Help One to Predict the Weather , but 
It Can Also Serve as a Real Factor in Decoration 
B. FRANCIS DASHIELL 
T HE barometer as an aid in the predict¬ 
ing of weather conditions is unexcelled, 
and with its aid the prediction of forth¬ 
coming weather can be made with reasonable 
accuracy. Weather predicting may seem to be 
a complicated task, and so it is if one follows 
the intricate methods of the Weather Bureau. 
But for all practical purposes, rough predic¬ 
tions can be made on the basis of a little un¬ 
derstanding and some serious study of the 
barometer, the sky and the winds. 
The first barometer was devised by an 
Italian scientist in Italy in 
1643. It has taken the name 
Torricellian Tube after the dis¬ 
coverer of the hydrostatic prin¬ 
ciple, the Italian Torricelli. It 
is a long column of mercury in 
a glass tube sustained and ex¬ 
actly balanced by the weight of 
the air. He demonstrated that 
this atmospheric pressure va¬ 
ries from day to day according 
to local weather changes. At 
sea level the air pressure is 14.7 
pounds to the square inch, and 
as such will just balance a 
column of mercury 30" high. 
From this fact is derived the 30" 
mark which is taken as normal 
on the scale of the barometer, either of the 
mercuric or aneroid type. The height of the 
mercury, therefore, becomes a measure of the 
external air pressure, and any changes in the 
pressure are instantly noted in the barometer. 
The aneroid barometer is of the metallic 
type and is the best type for the average home 
use. While it is not as sensitive as the mer¬ 
cury tube, it is neater and more convenient, as 
it can be placed anywhere in the house that a 
clock would ire placed and will look as neat 
and attractive. Its location will make no dif¬ 
ference, but it should not be exposed to un¬ 
necessary heat or closeness. 
The barometer indicates the coming weather 
because it registers the pressure of the air. 
When the pressure is low or falling the scale 
reads under the 30" mark, and w’hen it is ris¬ 
ing or high the scale will read over the mark. 
These changes of the reading are termed the 
“highs” and “lows” of the atmospheric pres¬ 
sure and can be seen printed on any weather 
map in concentric contours called isobars. 
Generally speaking, a low pressure area 
spread out over a certain section 
of the country is indicative of a 
storm, as storms are distur¬ 
bances with a center of low pres¬ 
sure in the atmosphere. Ac¬ 
cording to the season of the year 
a falling barometer indicates a 
storm with rain or snow within 
a short time. Its approaching 
speed is given by the barometer. 
The rapidity of the fall or 
rise of the barometer indicates 
several things. If it falls rapid¬ 
ly, the storm center is close by 
and will soon pass the point of 
observation with high winds or 
gales. This sudden drop in the 
(Continued on page 78) 
From the period of Louis XV comes this 
mercury barometer in carved and gilded wood. 
It is from the collection of the South Kensing¬ 
ton Museum. Cotirtesy of B. Altman & Co. 
In the form of a clock pendulum, this Louis 
XVI barometer is richly ornamented. It is of 
chased and gilded brass. From a collection in 
the Louvre. Courtesy of B. Altman & Co. 
An old French barometer that serves an important purpose in a furni¬ 
ture grouping, besides indicating what the weather will be hours, or 
even days, in advance. Courtesy of Mrs. Emott Buel 
