Royal Society. 219 
furface of the fea^'when at the fame time, at Llanerch, mJDen- 
bypire, about 15 miles eaft of Smwdorjy and fix from the fea, 
kveral foot above the furface thereof, by Mr. ^Davis's ftandmg 
barometer, it was about 29, 7! inches j and the air continued, 
both before and after, in the fame ftate. Hence Mr. Halky con- 
cludes, that the difference of the prefllire of the air on the lea, 
and on the top of Snowdon, is rather more than 3 inches 8 tenths. 
Sno^wdon was meafured by Mr. Capiveh and he found its height 
i240yards^ which, abating the height of the mercury, 3 mches 
8 tenths, may lerve for a ftandard, till a better be obtained on a 
higher place. 
A Yoyage from England To Conftantinople 5 by Dr. The. 
Smith. Phil. Tranf. N° 230. p. 597. 
yf^G. 5d, i66Sy we went on board the Sezan^ Tacht Jot 
•^^ the 'Do-wris, where we arrived the next day in the after- 
noon, and went on board the Leopard Frigate, Capt. O "Bryan 
commander, appointed to carry Sir Tianiel Harvey, HisMa- 
jefty's ambaffador, to the port of the Ottoman emperor at Con- 
ftantinople. Aug, 9th, we failed from the 'Do'wns, but were 
forced to anchor S. W. off the fouth Foreland 3 we carried a flag 
upon our main-top, after we come out of the Doims. Aug, 17th, 
in the morning we got to the weft o{ Portland -, but about noon, 
falling over part of the race of "Portland, where we met with a 
tumbling fea, we anchored at the N. W. part of the bay, over- 
againft the point that looks towards Weymouth-,, we went a-inore 
on the ifland, which feems to be but one continued rock, the loil 
inleveral places not being above 5 or 6 inches deep, yet the corn 
flourifhing enough 3 the caftle confifts of a double fortification, 
we did not ohlerve above 3 guns mounted 5 there is only one 
church and 4 villages in the whole ifland. Aug. 29th,^we got 
into 'Plymouth found; the citadel is built upon a rocK, with 
large counterfcarps and ballions. Aug. 20th, we weigaed out ot 
"Plymouth found, and made the Lizard, a promontory in Cor«- 
<iml', the Manacles, feveral rocks fo called, were very diitintay 
feen, it being then low-water, as alfo the Land^s Erid 3 the wind 
blew frelh, and we obferved the waves in the night-tirae, -is it 
they had been liquid fire, but palifli. Aug. 25th, we were tull 
open with the bay of Sifcay 5 leveral fea-gulls were feen hovering 
over the liarface of the water, to catch fiih which Iwam Dy m 
vaft fhoals, at above 50 leagues diftance from any land 3 at other 
times we faw feveral birds floating on the water, which, being 
driven by Ibrae tempeft from the coafts of Spain and "^^^^^'^ 
£ e 2 
