In a light wind of five or six yards a second they still moved.
But nothing practical had been obtained.

Against a miller's wind--nine yards a second--the machines had remained almost stationary.
Against a fresh breeze--eleven yards a second--they would have advanced backwards.

In a storm--twenty-seven to thirty-three yards a second--they would have been blown about like a feather.

In a hurricane--sixty yards a second--they would have run the risk of being dashed to pieces.

And in one of those cyclones which exceed a hundred yards a second not a fragment of them would have been left.
It remained, then, even after the striking experiments of Captains Krebs and Renard, that though guidable aerostats had gained a little speed, they could not be kept going in a moderate breeze.