We stopped the electrical ship at an elevation of perhaps three hundred feet above the vast roof of a structure which Aina assured us was the building of which we were in search.

Here we remained for a few minutes, cautiously reconnoitering. On that side of the power house which was opposite to the shore of the Syrtis Major there was a thick grove of trees, lighted beneath, as was apparent from the illumination which here and there streamed up through the cover of leaves, but, nevertheless, dark and gloomy above the tree tops.

"The electric network extends over the grove as well as over the building," said Aina.

This was lucky for us, because we wished to descend among the trees, and, by destroying part of the network over the tree tops, we could reach the shelter we desired and at the same time pass within the line of electric defenses.

With increased caution, and almost holding our breath lest we should make some noise that might reach the ears of the sentinels below, we caused the car to settle gently down until we caught sight of a metallic net stretched in the air between us and the trees.

After our first encounter with the Martians on the asteroid, where, as I have related, some metal which was included in their dress resisted the action of the disintegrators, Mr. Edison had readjusted the range of vibrations covered by the instruments, and since then we had found nothing that did not yield to them. Consequently, we had no fear that the metal of the network would not be destroyed.

There was danger, however, of arousing attention by shattering holes through the tree tops. This could be avoided by first carefully ascertaining how far away the network was and then with the adjustable mirrors attached to the disintegrators focusing the vibratory discharge at that distance.

So successful were we that we opened a considerable gap in the network without doing any perceptible damage to the trees beneath.

The ship was cautiously lowered through the opening and brought to rest among the upper branches of one of the tallest trees. Colonel Smith, Mr. Phillips, Mr. Edison and myself at once clambered out upon a strong limb.

For a moment I feared our arrival had been betrayed on account of the altogether too noisy contest that arose between Colonel Smith and Mr. Phillips as to which of them should assist Aina. To settle the dispute I took charge of her myself.