"Yes," he continued, "there is one way of checking the dissolution of the ice-there is one way of saving us all."
All gathered eagerly round the speaker, and looked at him inquiringly. They thought they must have misheard what he said.
"Well!" asked Hobson, "what way do you mean?"
"To the pumps!" replied Black simply.
Was he mad? Did he take the ice for a sinking vessel, with ten feet of water in the hold?
The air pumps were at hand, together with the air vessel, which Hobson had been using as a reservoir for drinking water, but of what use could they be? Could they harden the ice, which was melting all over?
"He is mad!" exclaimed Long.
"To the pumps!" repeated the astronomer; "fill the reservoir with air!"
"Do as he tells you!" cried Mrs Barnett.
The pumps were attached to the reservoir, the cover of which was closed and bolted. The pumps were then at once set to work, and the air was condensed under the pressure of several atmospheres. Then Black, taking one of the leather pipes connected with the reservoir, and opening the cock, let the condensed air escape, walking round the ice wherever it was melting.