288 
equipped boiler works in the world 
was unable ‘‘to handle the problems 
connected with the pneumatic sys- 
tem of water supply.” Presumably, 
one of the chief problems was the 
Spraying the lawn by pneumatic pressure 
construction of the tank. This same company makes use of 
special machines for calking and riveting. With an abso- 
lutely tight tank, one great difficulty is overcome. ‘The other 
large difficulty concerns the pumping. If one thinks a mo- 
ment he will readily see that as the air pressure in the tank 
increases the work of the pump becomes more severe. It 
has to overcome the resistance of the water in the tank, and 
this water is under the pres- 
sure of the air. In conse- 
quence of the work which 
the pump has to do, 
its parts will have to be 
very strong and the joints 
will have to be especially 
tight. Whatever the pres- 
sure of the air in the tank, 
that is the pressure of the 
water in the pump trying to 
get out. The pump, then, 
must be a fine and strong 
piece of work—no better, 
perhaps, than a pump 
which raises water to an 
elevated tank whose level 
corresponds to the air pres- 
sure. 
What seems to be a very 
fine thing about the pneu- 
matic water supply system is 
that there is absorption of air by the water pumped in. This 
is due, no doubt, largely to the pressure. Air, as pretty much 
everybody knows, contains free oxygen; and oxygen is a 
great enemy of impurity. In consequence, the water in the 
tank will, no doubt, be 
benefited. Further, water 
that contains plenty of air 
is fresher and more pala- 
table. Water supplied by a 
high-pressure pneumatic 
system will be filled with 
air bubbles as it comes from 
the spigot. The water at 
first has a milky appear- 
ance; but this quality 
passes, and water well aer- 
ated is what we finally 
have. 
The absorption of air by the water will, of course, in 
time reduce the amount acting as a pressure cushion. It is 
necessary, therefore, to replace the air thus absorbed and 
carried off with the water. This is accomplished automatic- 
AMERICAN HOMES 
Two streams may be thrown over 
the house, using 1'/y inch hose 
and !4 inch nozzles 
Two pneumatic tanks are installed in the basement of this house 
The larger tank is supplied from the well containing hard water; the 
smaller one from a cistern containing soft water 
AND GARDENS August, 1911 
ally in an ingenious way. There is 
a hollow cylinder made of metal 
and sealed. ‘This floats on the sur- 
face of the water. By an arrange- 
ment of rods, it is connected with 
ve 
Fifteen sprinklers can be run at one time 
a valve which opens and closes an orifice opening to the 
outer air. When the height of the water in the tank is just 
right to have an air cushion of the proper size above it, the 
valve is closed and no air can enter through the orifice. This 
means that no additional air will be drawn into the pump. 
But when the air cushion gets smaller and the water level 
rises in consequence, the float rises too and opens the valve. 
Air is now drawn into the 
pump and then pumped into 
the tank. Here, the most 
of it will rise to the surface 
and join the air cushion. 
As the tank of a pneu- 
matic system is more safely 
and advantageously situ- 
ated on the ground level, or 
even below it, we can if de- 
sired increase our pressure. 
Of course, the tank must be 
strong and tight enough. 
and the pump and the avail- 
able power must be suf- 
ficient. Under such condi- 
tions, we can add to our 
pressure. A water tower 
once constructed would be 
rather difficult to elevate. 
It is rather easy to pro- 
tect the tank against cold. 
This may be important for reasons other than those con- 
nected with freezing. It would seem better to deliver water 
somewhat less cold than would be possible with an exposed 
tank. It would seem, too, that in many cases the repairs 
would be greater with the 
elevated tank. If mounted 
on exposed steel work, a 
good deal of painting will 
have to be done from time 
to time. Sometimes the 
elevated tank is put into the 
attic or other high parts of 
the house itself. In case 
of fire, the elevation would 
be insufficient to provide a 
very effective stream of 
water. During the fire, the 
tank supports may fail and 
all help from this source vanish. If the tank system is used 
at all, there should be a special tower high enough to provide 
a good strong stream rising higher than the ridge pole. It 
is all very simple with the pneumatic system; any reasonable 
