DAVY’S EXPERIMENTS AND OBSERVATIONS, XC. 
Great Norey with the Mode used in reco- 
vering her. By Mr., Joszpn WHIDBEY, 
Master. Attendant,in Sheerness Dock-yard. 
At eight o’clockin the morning of the 
’ Oth of July, 1801, the Dutch frigate Am= 
buscade left the moorings in Sheerness 
harbour, her fore:sail, top-sails, and top- 
gallant sails being set,;with the wind aft 
blowing strong. In about thirty mi- 
nutesshe went down by.the head, near 
the»Great Nore; not giving the crew 
time to take in the sails, nor the pilot or 
officers;more than four minutes notice 
“before she sunk, by which unfortunate 
event twenty-two of the crew were 
drowned. . 
This extraordinary accident was owing 
to the hawse-holes being extremely large 
and Jow, the hawse-plugs not being in, 
and the holes being pressed under water 
by a crowd of sail on the ship, through 
which a sufficient quantity of water got 
in, unperceived, to carry her to the bot- 
tom. 
The vessel, though sunk, having sus- 
tained no external injury, it became an 
object of importance to weigh her up; 
this, was successfully effected by Mr. 
Whibbey, by means of lighters, in an in- 
genious manner, but incapable of being 
understood without a reference to the 
plate. 
14. Olbservadions on a new Species of hard 
Carlonate of Lime ; also on a new Species 
of Oxide of Fron. By the Count De Bour- 
won, F328. 
The carbonate of lime here described 
is inthe form of hexahedral pyramids, 
is so hard as to scratch with great ease 
fluor-spar, and even to take off the polish 
of glass; it possesses a vitreous fracture, 
and cannot be teduced to thé primitive 
rhomboid ;_ Mr. Chenevix analyzed it, 
but found its composition to differ in no 
respect from the softer carbonate. ‘The 
iron ore crystallizes im perfect cubes, is 
not affected by the magnet, and holds a 
middle station between the attuactable 
octahedral ifon ore and the hematites. 
15. Account of the Changes that have hup- 
pened: during the last Twenty-five Years 
an the relative Situation of Doulle Slars, 
withan Investigation of the Cause to which 
they ure cwing. By WittiaM Herscnuer, 
LL.D.F.RS. 
‘ 
The object of this interesting paper, 
which, from the minuteness of its details, 
is incapable of being abstracted, is to 
shew the probability, that many of the 
Ann. Rev. Vor. II. 
897 
apparently double stars are real binary 
combinations, held together by their mu- 
tual attraction. 
16. An Account of the Measurement of an 
Arc of the Meridian, extending to Dunnose 
in the Isle of Wight, latitude fifty degrees, 
thirty-seven minutes, cight seconds, to Clif- 
ton in Yorkshire, latitude fifty-three degrees, 
twenty-seven minutes, thirty-one seconds, 
in Course of the Operations carried on for 
the Trigonometrical Survey of England in 
the Yeurs 1800, 1801, and 1802. By Ma- 
jor W. Mupas, of the Royal Artillery, 
F.R.S. 
Major Mudge is well known as the 
able successor to General Roy in the 
important work of carrying on the tn- 
gonometrical survey of England. “the 
memoir before us, though of vast con- 
sequence, is from its very nature incapa- 
ble of abridgment. The first part is oc- 
cupied by a very minute description of the 
zenith sectoremployed by Major Mudge, 
and the last specimen of the accuracy 
and ingenuity of the late Mr. Ramsden. 
To this succeeds an account of the opera- 
tions in the year 1802, consisting of ob- 
servations at Dunnose, the southern ex- 
tremity of the meridian line at Clifton, 
near Doncaster, its northern extremity 5 
and at Arbury Hill and the intermediate 
stations. In 1801 a base 26342.7 feet 
long was measured on Misterton-carr, 1m 
the north-west corner of Lincolnshire, 
being the fourzh that has been ascertain- 
ed in the progress of the survey (the 
three others were on Hounslow Heath, 
Salisbury Plain, and Sedgemoor. ) 
The ascertained distance between Dun- 
nose and Clifton amounts ‘te 1036334 
feet or 196.27 miles; between Dunnose 
and Greenwich 59.41 miles, and between, 
Clifton and Greenwich 136.86 miles. 
The length of a degree on the meridian, 
latitude fifty-two degrees, two minutes, 
twenty seconds, is = 60820 fathoms, and 
ofa degree, in latitude fifty-one degrees, 
thirty-five minutes, eighteen seconds, is 
= 60864 fathoms. By combining the 
observations of the English and French 
astronomers we have a series of triangles 
from Clifton to Barcelona in Spain, and 
the distance between the two. places 
amounts to 4411968 feet or 835.6 miles. 
As an appendix to the memoir are sub- 
joined the Jatitudes and longitudes of 
the places intersected in the survey of 
Essex, ‘Suffolk, Surry, Middlesex and 
Kent. sl ee oe 
8 M 
