ttle
screw in the pipe, the gas will keep pouring out into the room all the
time, and if it isn't disposed of by being burned up, it will mix with
the air and make it poisonous to breathe. A man at the hotel here, a few
nights ago, blew out the gas because he did not know any better, and was
almost suffocated before he realized the trouble and opened his window."

"And where does the gas come from in the first place?" pursued Kitty.

"Why, from the gas-works, of course," said Philip in a very superior way,
for he was a year the elder of the two. "That brick building over by
Miller's Hill--don't you know--that we pass in going to Aunt Hester's."

"I know that as well as you do, Philip Lawrence," said Kitty with some
dignity. "What I wanted to know was what it's made out of. What is it,
papa?"

"Out of coal," said papa. "They put the coal in ovens and heat it till
the gas it contains is separated from the other parts of the coal, and
driven off by itself. Then it is purified and made ready for use."

"Out of coal? How funny! I wish I could see all about it," said Philip,
looking more interested.

"And so do I wish I could," added Kitty.

"I don't see why it cannot be done," said papa. "If you really care to
see it, and won't mind a few bad smells, I will ask Mr. Carter to-morrow
morning, when he can take you around and explain things."

The next day when Mr. Carter was asked about it, he said, "O, come in any
day you like. About three in the afternoon would be a good time, because
we are always newly-filling the retorts then." This sounded very nice and
imposing to the children, and at three the next afternoon they started
out with papa. The gas-house certainly did smell very badly as they drew
near it, and dainty Kitty sniffed in considerable disgust. Philip
suggested that perhaps she had better not go in after all; he didn't
believe girls ever did go into such places. And upon that Kitty valiantly
declared she did not mind it a bit, and sternly set her face straight.

[Illustration: A RETORT.]

Mr. Carter met them at the door. "You are just in time to see the retorts
opened," said he, and led the way directly into a large and very dingy
room, along one side of which was built out a sort of huge iron cupboard
with several little iron doors. The upper ones were closed tight, but
some of the lower ones were open a crack, and a very bright fire could be
seen inside. Everything around was dirty and gloomy, and thes