170 
LETTERS FROM THE REV. WM. DERHAM, D.D 
is well printed. I beg the favour of my humbel service to Your 
Lady, Son and Daughters, & am 
Cr 
Your most humble servant 
W. Derham. 
I forgot to tell you y* a Bell hung in the Rec r . of the Boylear 
Engine, gave a very audible sound before exsuction, but as the Air 
was pumped out the sound grew more languid, so at last we could 
scarce hear it at all. 
The Doctor returns some books and asks for the loan of 
three others, viz., a number of the Royal Society’s Transactions 
which it may be noted Dacre appears to have taken in before 
he became a member, and also Plot’s Natural History of Staff¬ 
ordshire, and Mr. (after Sir Isaac) Newton’s book on optics. 
The Rev. Dr. Plot, 1640-1696, was born in Kent and educated 
at Oxford, where he obtained the degree of D.C.L. in 1671 and 
became keeper of the Ashmolean Museum. He is said to have 
been very witty and a bon vwant. E. Lhuyd, who succeeded him 
as keeper of the Museum, said “ he had as bad morals as ever 
characterised a Master of Arts.” 
Plot wrote the Natural History of Oxfordshire in 1676 ; in 
1682 he was appointed secretary to the Royal Society and in 
1686 he published the above mentioned book, which Dr. Derham 
wanted to borrow, and which is a better work than his previously 
written history of Oxford. 
Mr. Isaac Newton is too well known to require any remarks 
here, but it may be mentioned that his book on what the Doctor 
called “ Opticks,” which was written in Latin, was published 
only in 1704, so that if Dacre had obtained a copy as early as 
June, it shows how eager he must have been to obtain the most 
recent scientific works. 
The decided, although erroneous, opinion of Newton that it 
was not possible to make any important improvement in re¬ 
fracting telescopes led him to turn his attention to reflecting 
ones ; the largest telescopes now in use are constructed on the 
principle of refraction. 
The Lord Halifax, 1661-1715, mentioned as being present 
at the meeting of the Royal Society, was Charles Montagu, 
created Baron Halifax 1700. One of the most prominent men 
of his time, he was Chancellor of the Exchequer and First Lord 
of the Treasury in the reign of William III. Although he was 
