The more he thought of his own descent into that great cleft, the more he thought of the horrible danger of sliding down some invisible declivity to awful, unknown regions; the more he thought of the mysterious death of Rovinski, the more firmly did he determine that not by his agency should a human being descend again to those mysterious depths.

He would do all that he could to enable men to see into the interior of this earth, but he would do nothing to help any man to get there.
The controversies in regard to their discoveries and theory disturbed Roland and Margaret not a whit; they worked steadily, with energy and zeal, and, above all, they worked without that dreadful cloud which so frequently overhangs the laborer in new fields--the fear that the means of labor will disappear before the object of the work shall come in view.
One morning in the early summer, Roland rushed into the room where Margaret sat.
"I have made a discovery!" he exclaimed.

"Come quickly, I want to show it to you!" The heart of the young wife sank.

During all these happy days the only shadow that ever flitted across her sky was the thought that some novel temptation of science might turn her husband from the great work to which he had dedicated himself.

Much that he had purposed to do, he had, at her earnest solicitation, set aside in favor of what she considered the greatest task to which a human being could give his time, his labor, and his thought.