that arose from it.

"That's exactly what it is, the 'river's breath,'" said Mr. Elmer.
"Warm air is lighter than cold, and consequently always rises; and
the warm, damp air rising from the surface of the river into the
cold air above is condensed into vapor, just as your warm, damp
breath is at this very moment."

"But I should think the water would be cold with all that ice
floating in it," said Mark.

"It would seem cold if we were surrounded by the air of a hot
summer day," answered his father; "but being of a much higher
temperature than the air above it, it would seem quite warm to you
now if you should put your bare hand into it. We can only say that
a thing is warm by comparing it with something that is colder, or
cold by comparison with that which is warmer."

When Mark and his father went down to breakfast they found the
rescued man still wrapped in blankets, but talking in a faint
voice to the captain; and at the table the latter told the Elmers
what he had learned from him.

His name was Jan Jansen, and he was a Swede, but had served for
several years in the United States navy. On being discharged from
it he had made his way to New Sweden, in the northern part of
Maine; but, a week before, he had come to Bangor, hoping to obtain
employment for the winter in one of the saw-mills. In this he has
been unsuccessful; and the previous night, while returning from
the city to the house on its outskirts in which he was staying, he