of a gas jet. It was conducted, by means of glass
pipes, to every dwelling in the city. One factory supplied sufficient
heat for over half a million inhabitants.

I thought I was not so far behind Mizora in a knowledge of heating with
hot air; yet, when I saw the practical application of their method, I
could see no resemblance to that in use in my own world. In winter,
every house in Mizora had an atmosphere throughout as balmy as the
breath of the young summer. Country-houses and farm dwellings were all
supplied with the same kind of heat.

In point of economy it could not be surpassed. A city residence,
containing twenty rooms of liberal size and an immense conservatory, was
heated entire, at a cost of four hundred centimes a year. One dollar per
annum for fuel.

There was neither smoke, nor soot, nor dust. Instead of entering a room
through a register, as I had always seen heated air supplied, it came
through numerous small apertures in the walls of a room quite close to
the floor, thus rendering its supply imperceptible, and making a draft
of cold air impossible.

The extreme cheapness of artificial heat made a conservatory a necessary
luxury of every dwelling. The same pipes that supplied the dwelling
rooms with warmth, supplied the hot-house also, but it was conveyed to
the plants by a very different process.

They used electricity in their hot-houses to perfect their fruit, but
in what way I could not comprehend; neither could I understand their
method of supplying plants and fruits with carbonic acid gas. They
manufactured it and turned it into their hot-houses during sleeping
hours. No one was permitted to enter until the carbon had been absorbed.
They had an instrument resembling a thermometer which gave the exact
condition of the atmosphere. They were used in every house, as well as
in the conservatories. The people of Mizora were constantly
experimenting with those two chemical agents, electricity and carbonic
acid gas, in their conservatories. They confidently believed that with
their service, they could yet produce fruit from their hot-houses, that
would equal in all respects the season grown article.

They produced very fine hot-house fruit. It was more luscious than any
artificially ripened fruit that I had ever tasted in my own country, yet
it by no means compared with their season grown fruit. Their preserved
fruit I thought much more natural in flavor than their hot-house fruit.

Many of thei