286 
tance above the 
| highest point of use 
in the house. 
The size of the 
reservoir is also an 
important matter. 
If the supply is 
liable to fluctuation, 
as is ordinarily the 
case, then the reser- 
voir must be at least 
big enough to tide 
oven the longest 
period of drouth. 
In fact, it should be 
larger than the ca- 
pacity necessary to 
cover the maximum 
a “dry spell,” forthe 
Fig. 2—A brick tower with reason that the res- 
hidden by the wall ervoir may not be 
full, or nearly full, when the drouth begins. Indeed, the 
wise thing would seem to be to have a capacity nearly double 
the amount for the drouth, so that a sufficient supply would 
be certain to be present when it began. 
The support of a large body of water at a considerable 
height is really a serious problem, and expert advice ought 
ordinarily to be sought. In order to realize just what kind 
of a problem this is, consider the fact that the water which 
fills a 10,000-gallon tank weighs 83,000 pounds. Ten thou- 
sand gallons for a family using 500 gallons per day will only 
last twenty days. The support for 83,000 pounds must, of 
course, be a thoroughly adequate one. The tower may be 
of steel or it may be of reinforced concrete. Timber, brick 
or stone may be used. In any case, the total weight of 
water and tank must be thoroughly faced and provided for. 
As to the strength of the tank itself, we have to remember 
that the water exerts a bursting pressure tending to disrupt 
the side walls. The bursting pressure ranges from nothing 
at the water level to a maximum at the bottom. If the 
bottom is ten feet below the level of the water, there will 
be a bursting pressure out- 
ward at that point of four 
and one-third pounds per 
square inch. A considera- 
tion of such facts will show 
that the tank must be 
strengthened to resist the 
outward impulse, and that 
the strength should increase 
toward the bottom. 
The tank may be of 
wood, steel or reinforced 
concrete. In hie. a swe 
have an example of tower 
and tank. The tower is 
built of brick. As here, the 
tower, with its mantle of 
foliage, may be a beautiful 
addition to the picturesque- 
ness of the grounds. Where 
the tank is of wooden 
staves, as in this instance, 
the metal hoops may be 
provided with turnbuckles, 
so that they may be tight- 
ened at will. The hoops 
may be placed closer and 
closer together toward the bottom; or if it is desired to 
have them at uniform intervals, this may be done. But the 
interval necessary at the bottom will control. Or equal 
the tank 
AMERICAN HOMES AND GARDENS 
Fig. 4—The tower is built in connection with the stable 
TOT 
spacing may be em- 
ployed where the 
thickness of the 
hoops is adjusted to 
the varying pres- 
sures. 
In Fig. 2 we have 
another example of 
the brick tower. 
Here the tank is en- 
veloped and hidden 
by the wall. At the 
top, such a tower 
may be designed to 
provide an observa- 
tion room. In Fig. 
3 1s shown still an- 
other example. The 
envelope is a frame ~~ 
one. It is not ob- Fig) 3—-A wooden tower with the tank 
vious whether the bide Mya eE! 
tank is supported by timbers or by masonry. Fig. 4 shows 
yet another tower and tank. There is an observation bal- 
cony, giving an ornamental character to the tower and 
affording a view in all directions. 
At Great Neck, L. I., on the grounds of Mrs. B. H. Gil- 
bert, is a tall tower of wood covered with stucco. This sup- 
ports a tank having a capacity of fifteen or twenty thousand 
gallons at an elevation of perhaps seventy feet. This puts 
the water well up above the ridge of the house, and thus 
provides a good flow in the upper rooms. The balcony is 
gained from the outside,“as shown in the view (Fig. 8). In 
Fig. 6 we have a wooden exterior in the form of a windmill. 
It is not always necessary that the tower itself shall be high. 
It will sometimes stand on a local elevation of the ground, 
although that may not be the case here. In Fig. 7 we have 
the same tower used for the support of the tank and for the 
accommodation of a windmill. 
In case the water tower and tank are in service during 
the entire year, the resident in the Northern States may need 
to consider the question of freezing weather. The presence 
of a layer of ice may be no 
great matter under some 
conditions. In many struc- 
tures it may seem desirable 
x to prevent absolutely all 
freezing. This can be done 
by suitably enclosing the 
tank and surrounding it 
with a good non-conductor 
of heat—one of sawdust or 
tanbark. 
The methods employed 
with the elevated tank are 
time-honored and have had 
extensive application. An- 
other system, however, has 
come into vogue in recent 
years. It is the pneumatic 
tank system. Apparently 
this invention was made by 
Mr. J. L. White, 9iime 
reservoir is not elevated at 
all. A pressure there must 
needs be, and this is sup- 
plied by compressed air. 
Essentially, Mr. “White’s 
system is very simple. He 
pumps water into an air-tight reservoir. The contained air 
is crowded into a continually decreasing space as the amount 
of the incoming water grows greater and greater. If the 
