JOHN DEE 239 
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 re- 
quested 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 arch- 
bishop 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 mathe- 
maticians, 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 manu- 
scripts 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 undemonstrated 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 
