That would carry fire, as well as a vessel of either cast or wrought iron--at least sufficient to serve for a short excursion such as we should care to make.

Now-a-days, fire is not used for inflating balloons.

Inflammable gas has been found to be far superior for this purpose; but as we have no such thing in stock, we should have to proceed on the old original plan--that employed by the brothers Montgolfier--the first inventors of the balloon." "You think, then, that the fire apparatus could be dispensed with, if we could only discover some material that would make the great globe-shaped bag to contain the heated air ?" "Ay," replied Karl; "think of something to do that, and I promise to make you a balloon." Thus challenged, Caspar set his wits to work; and for a long while he sat in silence, as if buried in some very profound speculation.
Probably, there was no material substance in that valley that did not pass in review before the retina of his mental vision; and all were considered in turn.
"It must be light, air-tight, and strong ?" asked he, at length, as if there was something in his thoughts possessing these three requisites.
"Light, air-tight, and strong," answered Karl, simply repeating his words.
"The two last I am sure of," rejoined Caspar.

"Of the first only have I my doubts." "What is it ?" asked Karl, in a tone that betrayed his interest in what Caspar had said.
"Eel-skins!" was the laconic answer..