Davy's life was now an extremely busy one. He published, when he was twenty-one, his "Essays on Heat and Light," beginning his work, like Sir Isaac Newton, when but a youth. He discovered silica in the epidermis of the stems of weeds, corn, and grasses. He found the intoxicating effects of breathing nitrous oxide, April 9, 1799, and his experiments on this subject were published the following year. He spent ten months of incessant labor in them, often endangering and once nearly losing his life from breathing carburetted hydrogen. He made experiments on galvanic electricity, increasing the powers of the Galvanic Pile of Volta. He also planned and partly wrote an epic poem on the deliverance of the Israelites from Egypt. Worn with overwork, he returned to see his widowed mother at Penzance. He had been absent a year. How glad were all to greet the rising young scientist! Not least glad was Davy's water spaniel, Chloe. When very small, and about to be drowned, he begged her as a gift, and with great care reared her to be his hunting and fishing companion. At first she did not know him, but when, with his peculiarly musical voice, he called her by name, "she was in a transport of joy." Davy never forgot his early life at Penzance. In his will he left a sum of money to be paid annually to the master of the grammar school, "_on condition that the boys may have a holiday on his birthday_." One secret of Davy's early success was, no doubt, his ambition. He used to say that he had been kept largely from the temptations of youth by "an active mind, a deep ideal feeling of good, and _a look towards future greatness_." The young man or woman who definitely plans to be somebody seldom finds any obstacles along the road too great to be overcome. He wrote in his note-book: "I have neither riches, nor power, nor birth to recommend me; yet, if I live, I trust I shall not be of less service to mankind, and to my friends, than if I had been born with these advantages." At the Pneumatic Institution he found in Mrs. Beddoes "the best and most amiable woman in the world," a helper in the development of his genius. Like the wife of William Humboldt, and like any other woman who combines heart and intellect, Mrs. Beddoes gathered about her, in her home, Coleridge and Southey, and other bright minds of Clifton. Here Davy, scarcely more than a boy, with his soft brown curling hair, his beautiful smile, and his "wonderfully bright eyes, which seemed almost to emit a soft light, when animated," in the midst of congenial friends, was stimulated to do his best. Years after this, Wordsworth gave Dr. John Davy a letter to Coleridge, on the back of which he had written: "This from Davy, the great chemist. It is an affectionate letter."