"But by what agency does man achieve the mastery of Nature? By the agency of heat. By the aid of heat man subdues the world. Heat brings the lustrous metal from its native ore; heat fashions the metal into a thousand shapes for the use of men; heat reigns as king in the curious processes of the chemist's laboratory, and the laboratory is the mother of all those modern arts which bless and beautify human life. By heat man prepares his food; by heat he drives his machinery; by heat he outstrips the flight of the winds; by heat he turns winter into summer and in his own dwelling makes for himself a perpetual springtime. For these purposes of human comfort and culture, God has provided generous stores of heat and placed them under man's control. He has placed in man's hands the means by which he can generate a heat which devours the hardest metals like stubble and a cold greater by far than Nature ever produces. We see that the Creator has provided for man as a being susceptible of culture and development, as a being of soul and sentiment, of spirit and aspiration. God has fitted the world to be the dwelling-place of spiritual beings like man." "I beg your pardon," said Mr. Hume at this point, "that the first word I speak in your class should be a question which amounts to an objection." "I shall be glad," said Mr. Wilton, "to hear your question, even though it be an objection. I will also answer it if I can." "I wished to ask why it is, if God designed to provide for man's wants, that man can supply his wants, especially his higher wants--the wants of his intellectual and spiritual nature--only with the greatest difficulty and toil? The brutes supply their need with comparative ease, but man with boundless thought and labor."