himself wrote two works on navigation). The East India Company called upon him to improve the compass. Certain large landholders in England who had mines extending under their boundary lines came to him to settle their controversy. In 1582 Dee was urging the Queen to improve the calendar, and two years later she and her ministers requested him to make the necessary calculations. The Roman Church amended the calendar on the supposition that all that was done at the council of Nice with regard to chronology was correct and proposed the omission of ten days, but Dee's calculations led him to recommend the omission of eleven days. He agreed, however, to compromise for the sake of uniformity, providing the facts should be publicly announced. The plans were approved by the lay members of the committee, Thomas Digges, Henry Savile and Mr. Chambers, but opposed by the archbishop and bishops on the ground chiefly that the project of reforming the calendar emanated from the See of Rome. The reform was thus delayed one hundred and seventy years, but Dee's able treatise was preserved and was made use of when the change actually took place. The original has passed through the hands of many eminent mathematicians, and is now in the Ashmole collection at Oxford.
This treatise on the calendar, the "Fruitful Preface" and the memorial to Queen Mary in regard to a royal library are the most significant of his seventy-nine works, many of which were never printed. In the last-named Dee called the queen's attention to the fact that with the destruction of the cloisters there was no longer any place of safety for manuscripts, and that these were now being destroyed or scattered broadcast. He set forth the loss this would be to history and science, and proposed that a commission should be appointed to establish a royal library—he himself undertaking to procure copies of famous manuscripts at the Vatican. Whether because of his youth or because of the indifference of the Queen, he was not listened to, but in his own library at Mortlake he collected 4,000 books, of which he tells us "700 were ancient manuscripts in Greek, Latin and Hebrew."
John Dee early accepted the Copernican theory and was apparently among the first to understand and give due weight to the writings of Roger Bacon, to whom he refers as a "philosopher of this land native (the floure of whose worthy fame, can never dye nor wither)." It was to him doubtless that Dee owed his high valuation of experiment in science. He begs of his readers to
Esteeme one Drop of Truth (yea in Natural Philosophie) more worth, than whole Libraries of Opinions undemonst rated or not answering to Nature's Law, and your experience. . . . Words and arguments are no sensible certifying: nor the full and final frute of Sciences practisable.
That many of the opinions held by Dee were not common among even the learned of his countrymen is evident from the manner in which he exhorts them in his writings. He too held out a hand to "divine
