This intimate acquaintance with Whitefield forms something like a bond of union between Franklin and his only intellectual compeer, Jonathan Edwards; and the different attitude of the two men towards the wandering revivalist is a good illustration of the great contrast in their characters. If Franklin may in some ways be called the typical American, yet the lonely, introverted, God-intoxicated soul of Edwards stands as a solemn witness to depths of understanding in his countrymen which Dr. Franklin's keen wit had no means of fathoming. But in one respect the two minds were alike: they were both acute observers of nature, and we have only to read Edwards's treatise on spiders, written when he was twelve years old, and to follow his later physical investigations, which indeed foreshadowed some of Franklin's electrical discoveries, to learn how brilliant a part he might have played in science if his intelligence had not been troubled by the terrible theology of the day. As for Franklin, we have seen the inquisitive bent of his mind in childhood, and as he grew older the habit of observing and recording and theorizing became his master passion. Though scarcely a professional scientist, his various discoveries in natural history and his mechanical inventions brought great renown to him as a man, and were even an important factor in the national struggle for independence. Nothing was too small or too great to attract his investigating eyes. All his life he was interested in the phenomena of health and in the care of the body, and even as a boy, it will be remembered, he had experimented in the use of a vegetarian diet. He had his own theory in regard to colds, maintaining that they are not the result of exposure to a low temperature, but are due to foul air and to a relaxed state of the body,--as in general they no doubt are. His letters are full of clever protests against the common theory, and at times he was brought by his opinions into amusing conflict with the habits of other persons. On one occasion in a tavern he was compelled to occupy the same bed with John Adams, who, being an invalid and afraid of night air, shut down the window. "Oh!" says Franklin, "don't shut the window, we shall be suffocated." Adams answered that he feared the evening air. Dr. Franklin replied, "The air within the chamber will soon be, and indeed now is, worse than that without doors. Come, open the window and come to bed, and I will convince you. I believe you are not acquainted with my theory of colds." Whereupon Adams got into bed, and the Doctor began an harangue upon air and cold, respiration and perspiration, with which the Bostonian was so much amused that he soon fell asleep and left Franklin and his philosophy together. The effect of drafts on chimneys was just as interesting to our philosopher as their effect on the human system, and it was one of his diversions when visiting the great houses of England and Europe to cure smoky fireplaces.