In the summer of 1822, he received proposals from R. H. Gardiner, Esq., of Gardiner, Me., to take charge of a new institution which he had determined to establish for the education of farmers and mechanics in the principles of science. Mr. Hale accepted, and closed his connection with Bowdoin College in 1822, and entering upon his duties January 1, 1823, opened the Lyceum, was inaugurated as its principal, and delivered an address on the occasion. He soon after returned his license, finding it inconvenient to meet the many calls for preaching extended to him, and having become also so settled in his preference for the Protestant Episcopal Church that he determined to take Orders therein, should he ever be so situated as to think it his duty to preach again. On the 9th day of April, 1823, he was married to Mary Caroline King, the eldest daughter of the Hon. Cyrus King, M. C.
The Lyceum soon attracted students and became a flourishing institution. Its principal gave lectures in Chemistry and taught Mathematics and Natural Philosophy, and in winter had classes in Architecture and in Agricultural Chemistry. For the former of these classes he prepared, in 1827, a work on the "Elementary Principles of Carpentry."
In July, 1827, having received an invitation to succeed Professor Dana in the chair of Chemistry at Dartmouth College, Mr. Hale accepted, and delivered his inaugural address on the day after Commencement. His esteemed and able colleagues in the Medical College were Reuben D. Mussey, M.D., Prof. of Anatomy and Surgery; and Daniel Oliver, M.D., Prof. of Theory and Practice of Medicine. It should be noted that at that period the importance of physical studies was not fully appreciated at Dartmouth. The college had not taken a scientific periodical in half a century. There was no cabinet of minerals. "There was not," writes Dr. Oliver, "a single modern volume in the college library upon either Mineralogy or Geology; and scarcely one, if one, upon Chemistry, later than the days of Fourcroy or Vauquelin. The prevailing taste was decidedly anti-physical. It was directed another way, and not only so, but there was among the college Faculty a disposition to undervalue the physical sciences." Dr. James F. Dana, the predecessor of Professor Hale, writing of the college in reference to physical science, used the following remarkable expression: "It was anchored in the stream, and served only to show its velocity." When Professor Hale was engaged, his duties comprised a course of daily lectures to the medical class through the lecture term, to which lectures the members of the Senior and Junior classes were to be admitted; and instruction to the Junior class in some chemical text-book by daily recitations for five or six weeks. This was all.