In 1847 he was appointed Professor of History in Munich. But his health not being very robust, though he accepted the chair, he was obliged a few months afterwards to resign. Fortunately, however, he received a similar appointment in the Lyceum of Bamberg, which he was able to maintain. This was his last. The _Grammatica Celtica_, which was to take the learned world by surprise and revolutionise Celtic studies, appeared in 1853, after thirteen years’ close and laborious work. It is written in Latin, and is so profoundly erudite that it has the reputation, like some other great German books, of being very difficult to grasp. The numerous sources consulted in the production of this masterpiece of scientific scholarship are all carefully given in the preface. Its publication at once established his fame, but the work killed him. In 1855 he was compelled to resign his chair through broken health. That same year Professor Siegfried of Dublin saw him, and afterward wrote the following interesting impression which the appearance of the devoted scholar made upon him. “I paid a visit,” he says, “to this remarkable man in the vacation of 1855, when his health was fast sinking. He was a tall, well-made, rather spare man, with black hair and moustache, giving on the whole more the impression of a Sclavonian or a Greek than a German.” He did not long survive his retirement, for in November 1856, less than three years after the completion of his Grammar, this illustrious linguist but modest and retiring man died in his native village in Bavaria. To him, mindful of his outstanding influence, Dr Whitley Stokes has not inaptly applied the Greek line— Ζεὺς ἀρχή, Ζεὺς μέσσα, Διὸς δ’ ἐκ πάντα τέτυκαι. After the publication of the _Grammatica Celtica_, Celtic studies received a mighty impetus and took great strides forward. Now that the Celtic dialects were proved to be Aryan, their further study became a necessity in connection with the comparative grammar of the whole family. Already in Germany there was the well-known _Zeitschrift für vergleichende Sprachkunde_ (Journal of Comparative Philology), a journal specially devoted to the Germanic, Greek and Latin languages; but now in 1856, the _Beiträge zur vergleichenden Sprachforschung_ (Contribution to Comparative Etymology) was started in Berlin to deal with the Aryan, Celtic, and Sclavonic tongues, and giving particular attention to the Celtic. The periodical went through eight volumes, one appearing in four parts every two years; and when it came to an end the _Zeitschrift_, edited by Dr. Kuhn, began to receive articles on Celtic subjects, and continues to do so still.