136 
drawing up a modell to regulate your 
travells by. As for particulars, these 
that follow‘are all that I now can think 
of: viz. q 
I, Whether “at ‘Semnitium, in Hun- 
gary (wheré*there are niines Of gold, 
copper, iron, Vitridl, antiniony, &c.) they 
changé iton ifito copper by dissolving it 
in a vitridlate Water, which they find in 
cavitys’ of rocks in the mines, and then 
melting the slimy solution in a strong 
fire, which in the cooling proves copper. 
The like is said to be done in other 
places, which I cannot now remember ; 
perhaps, too, it may be ‘done in Italy; 
for, about twenty or thirty years ‘agone, 
there was a certain vitrioll came from 
thence, called’ Roman vitrioll, but of a 
nobler virtue than that which is now 
called ‘by that name, which vitrioll is 
not now to be gotten, because, perhaps, 
they make @ greater gain by some such 
trick as turning iron into copper with it, 
than by selling ity’ 
II. Whether in’ Hungary, Sclavonia, 
Bohemia, near the town of Filia, or at 
the mountains of Bohemia, near Silesia, 
there! bee rivers whose waters are im- 
pregnated with gold; perhaps, the gold 
being dissolved by some corrosive waters, 
like aqua regis, and the solution carried 
along with the streame that runs through 
the niines ; ‘and whether the practice of 
laying mercury in the rivers till it be 
tinged with gold, and then straining 
the mercury through leather that the 
gold may stay behind, be a secret yet, 
or openly practised. 
- TIT. ‘There is newly contrived in Hol- 
land a mill to grind glasses plane with- 
all, and I think polishing them too} per- 
haps it will be worth ‘while to see it. 
IV. There is in Holland one Borry, 
who some ‘years since was imprisoned 
by the pope, in order to have extorted 
from him secrets, as I am told; of great 
worth, both ‘as to medicine and profit ; 
but he ‘escaped into Holland, where 
they ‘usually granted him a’ guard. I 
think he usually goes clothed in green. 
Pray mquire what you-can of him, and 
whether his ingenuity be any profit to 
the Dutch. You may inform yourself 
whether the Dutch have any tricks to 
keep their ships’ from being all’ worm- 
éaten in their voyages to the Indies; 
whether pendulum clocks do any service 
ini finding out the longitude, &c. : 
Tam weary, and I shall not stay to 
part with “a long complitrent; only I 
wish you a good journey, and God ‘be 
with’you; = * ‘ 
oe HES Isaac NeEwrTen. 
ae 
Remains of eminent Persons. 
[Sept. 1, 
Pray let us hear from you in your 
travells. Ichave given your two books 
to Dr, Arrowsmith: fees 
DR; MIDDLETON, Author of Free Enquiry, 
Life of Cicero, §e.: 
Sir—I esteem it:a very great honour 
to be allowed and, even commanded to 
usel.the same liberty, with you. by letter, 
which had given.me so. much pleasure in 
person, of conversing-.with,,you still at 
this distance; and. of, testifying more 
especially at this time, my most sincere 
and grateful acknowledgment of the late 
generous reception and uncommon 
marks of friendship, with which you 
were pleased to honour me in town. 
As to my remarks, they have been 
received here, as well as I could wish, 
nor have given any new or particular 
offence) that I hear of, but to such only 
as dislike the whole. Dr. Morgan, our 
Vice-Chancellor, with several more of 
the heads, likes them véry well, and is 
much my friend, so that whatever storms 
may blow up hereafter, I amin’ port at 
least for his reign. Tam very sensible, Sir, 
that they have given the less’ disgust, 
for the great patience you had in suffer- 
ing them to'be read to you, and the cor- 
rections they underwent by your autho- 
rity and direction. This I shall always 
reflect upon’as a singular proof of your 
great humanity as well- as great juds- 
ment, and am sorry only, that I had not 
so kind and so able ‘a monitor to’resort 
to on former occasions, to have made 
my other pieces more useful tothe: pub- 
lic, and less hurtful to!myself: but 
though I cannot recall what is past, yet 
T shall learn at least from the experi- 
. ence of your advice, how to weigh with 
more caution and prudence whatever 
may come abroad from me for the future. 
You’ see, ‘Sir, with what ‘confidence 
your great kindness has taught ‘me to 
treat you, when I dare venture to enter- 
tain you with’such trifles about myself; 
but if you can bear the impertinence of 
80 trifling a correspondenée, I shall not 
fail to give you part of whatever this 
place affords most considerable, and 
shall be industrious to’ pick up’ every 
thing worth your notice, for the oppor- 
tunity it will give me of signifying to 
yourself, what it will be my pride to 
signify to every body else, how much T 
am bound in honour and duty to approve 
myself on-all occasions with the utmost 
respect, Sir, your most obliged and most 
devoted'servant, © © 5 
; ; Conyers MippieTon. 
Camb, June 7tk 1733. eae 
Rosert 
