The point where we had dealt our blow was far removed from the great capitol of Mars, around the Lake of the Sun, and we knew that we should have to wait for the floods to reach that point before the desired effect could be produced. By the nearest way, the water had at least 5,000 miles to travel. We estimated that its speed where we hung above it was as much as a hundred miles an hour. Even if that speed were maintained, more than two days and nights would be required for the floods to reach the Lake of the Sun.
But as the water rushed on it would break the banks of all the canals intersecting the country, and these, being also elevated above the surface, would add the impetus of their escaping waters to hasten the advance of the flood. We calculated, therefore, that about two days would suffice to place the planet at our mercy.
Half way from the Syrtis Major to the Lake of the Sun another great connecting link between the Southern and Northern ocean basins, called on our maps of Mars the Indus, existed, and through this channel we knew that another great current must be setting from the south toward the north. The flood that we had started would reach and break the banks of the Indus within one day.
The flood traveling in the other direction, toward the east, would have considerably further to go before reaching the neighborhood of the Lake of the Sun. It, too, would involve hundreds of great canals as it advanced and would come plunging upon the Lake of the Sun and its surrounding forts and cities, probably about half a day later than the arrival of the deluge that traveled toward the west.
Now that we had let the awful destroyer loose we almost shrank from the thought of the consequences which we had produced. How many millions would perish as the result of our deed we could not even guess. Many of the victims, so far as we knew, might be entirely innocent of enmity toward us, or of the evil which had been done to our native planet. But this was a case in which the good--if they existed--must suffer with the bad on account of the wicked deeds of the latter.
I have already remarked that the continents of Mars were higher on their northern and southern borders where they faced the great oceans. These natural barriers bore to the main mass of land somewhat the relation of the edge of a shallow dish to its bottom. Their rise on the land side was too gradual to give them the appearance of hills, but on the side toward the sea they broke down in steep banks and cliffs several hundred feet in height. We guessed that it would be in the direction of these elevations that the inhabitants would flee, and those who had timely warning might thus be able to escape in case the flood did not--as it seemed possible it might in its first mad rush--overtop the highest elevations on Mars.