"I conclude, therefore, that God prepared this world as it now is as a place of discipline for a fallen race. This is the use to which he has devoted it in the past; and when there is no longer need of such a world for the discipline of men, we learn from the word of God that a 'new heaven and a new earth' shall be provided. This world is thus declared to be an unfit abode for the glorified saints. To judge, then, of the wisdom and goodness of God in the works of nature, we must keep in mind the object for which the Creator prepared the world. Ansel, tell us how this strikes you." "I never thought of it in this way before," he answered; "indeed I have thought very little of this subject, but--" Tinkle, tinkle went the bell upon the superintendent's desk. This was the second time the superintendent had struck his bell, but Mr. Wilton had been so intent upon his subject that he did not hear the first ringing. The school was dismissed, but Mr. Wilton remained with his class to fix upon the particular department of nature which they would study. He found that all were studying natural philosophy, and had recently gone over the subject of heat. At his recommendation, therefore, they agreed to examine, as a specimen of God's works, his management of heat in the world. Mr. Wilton requested them to review the subject during the week, and be prepared to state and apply the general principles touching the nature, phenomena, and laws of heat which they had already learned. This work they will enter upon next Lord's Day. CHAPTER III. A DIFFICULT QUESTION. During the week, Ansel, Peter, and Samuel were busy reviewing and fixing in memory what they had already learned of the nature and laws of heat. They were not only interested in the new line of study, and desirous of pleasing Mr. Wilton, but they also felt that their scholarship was to be tested, and each one was ambitious of standing equal to the best.