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
Sr.
Your most humble servant
W. Derham.
I forgot to tell you yt a Bell hung in the Rec. 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 vivant. 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