What a broadside of yells escaped from all these mouths, aimed at Robur like the muzzles of so many guns! Was not this hurling a declaration of war into the very camp of the balloonists?
Was not this a stirring up of strife between 'the lighter' and 'the heavier' than air?
Robur did not even frown.

With folded arms he waited bravely till silence was obtained.
By a gesture Uncle Prudent ordered the firing to cease.
"Yes," continued Robur, "the future is for the flying machine.

The air affords a solid fulcrum.

If you will give a column of air an ascensional movement of forty-five meters a second, a man can support himself on the top of it if the soles of his boots have a superficies of only the eighth of a square meter.

And if the speed be increased to ninety meters, he can walk on it with naked feet.