"What is that?" Tom inquired.
"In a storm. You know we can't always count on having good weather, and I'd like to see how she behaves in a gale."
"You shall!" declared the young inventor.
For the next week, during which finishing touches were put on the big craft, Tom anxiously waited for signs of a storm. At last they came. Danger signals were put up all along the coast, and warnings were sent out broadcast by the Weather Bureau at Washington.
One dull gray morning Tom roused his friends early and announced that the Mars was going up.
"A big storm is headed this way," Tom said, "and we'll have a chance to see how she behaves in it."
And even as the flight began, the forerunning wind and rain came in a gust of fury. Into the midst of it shot the big aerial warship, with her powerful propellers beating the moisture-laden air.