IT may be necessary to introduce this "faithful student of the school of verity," for his contribution to human thought was of the kind that is easily absorbed in the sum total of the period, while the man himself remains little known to any but his contemporaries. The writer's introduction to him was through his "fruitful preface" to the first translation of Euclid's "Elements" into English printed in 1570. That long preface is an interesting document in the development of intellectual freedom as well as in the history of science. It was addressed not so much to learned men as to the author's countrymen at large, though there was an occasional side glance at the university pedants. It expresses ideas strikingly like those for which the name of Francis Bacon stands, though written when Bacon was a boy of nine years. In it the author makes a vigorous appeal to the men of the time to shake themselves free from the commentational habit of the middle ages—to consider that the Greeks and Romans, who were held in such reverence, had not achieved all that was to be achieved. "Master Dee" was fully aware of the state of opinion that must be contended against. He says:

The immediate and ostensible purpose of the preface was to attract attention to the newly translated "Elements." The author begins:

In his pride in the achievements of England in the reign of Elizabeth, John Dee was at one with his countrymen, and whether consciously or unconsciously he appealed to men through the motive dominant in that period when he explained at great length how the "wonderful applications of mathematics" might be used for the glorification of the country. At the same time, the author sounds in advance a distinct seventeenth century note in suggesting that the laws governing natural phenomena might be better understood by being treated mathematically, and foreshadows the modern "Præcisions and Approximations-mathematik" when he speaks of "allowing somewhat