the Tube. The cars are not supplied with air from the tube. Fresh air is obtained from the evaporation of a semi-solid.
On the top of this Tube line there is a double railroad used for local travel, both passenger and freight
Their Storage Batteries.
Compared with our world, the fuel of Ploid is very scarce, but less is required to supply the industries. Nearly all power is obtained from the winds, running water and the sun's energy.
The winds are harnessed so that they blow not in vain. Almost every home of ordinary intelligence owns one of the many kinds of storage batteries used in this world. These batteries are usually located beneath the lowest floor of the house, and they constitute the reservoir whence is obtained the necessary power for lighting, heating and cooling the apartments of the home.
People who live along streams of water utilize these streams for similar purposes. It is now conceded in Ploid that the storage batteries of the home can be supplied as
