The confinement in the building since the middle of the previous day, however, was becoming irksome. The interpreter had not encouraged any suggestion about going out, and they had politely refrained from pressing the matter. Left to themselves after dinner, they decided to take a stroll outdoors. Robert had observed a secluded nook behind the palace. The windows of their bedchamber opened on this enclosure, which was entirely surrounded by a wall about twelve feet high. Apparently the wall was without any gate. A number of small trees marked the smooth lawn within, casting long shadows in the gathering twilight. It was in this nook that Robert proposed they take a stroll. As they reached the exit leading out upon the enclosure, one of their attendants appeared rather abruptly at a door to their left. He paused there a moment as if about to speak, then disappeared as suddenly as he had appeared. “So--we are under surveillance, eh?” remarked Professor Palmer. “I wonder. He did look at us rather suspiciously.” “Well, let’s go ahead and see whether they stop us.” But they were not molested as they stepped out upon the lawn. The cool dry air refreshed and invigorated them. It was free from the dampness of the dew which we are accustomed to feeling on our clear terrestrial nights, while the rarity of the Martian atmosphere was probably made up by a greater percentage of oxygen, as evidenced by the ease and enjoyment with which they breathed it. This they later affirmed. Tubercular diseases upon Mars were virtually unknown. In fact, the Martians were afflicted with little sickness of any kind. For perhaps fifteen minutes they walked about, smoking cigars from their slender store which they had carried from the _Sphere_ in their pockets. The fleeting Martian twilight was replaced by darkness--that is, if one can call night filled with the soft radiance of millions of stars “darkness.” Over the edge of the wall at the western end of the garden hung Phobus, one-half its disk lit in a dull orange glow. It appeared about one-quarter the size of our moon. A strange feeling of oppression, which he could not understand, possessed Robert. Try as he would he could not shake it off. Then he realized for the first time the intense silence which pervaded the night. There was a total absence of the countless sounds of nature which we are so accustomed to associating with summer nights. Apparently there were no insects upon Mars, or, if there were, they were voiceless. Their own voices startled them when they broke the stillness, and unconsciously they took to speaking in hushed whispers. A few feet to the right of their doorway the palace wall ran out into the garden at a right angle for about fifty feet, thence it again turned off at a right angle to the right. The garden ran around this extension and back into a recess on the other side like the lower part of a large letter L.