ÖÖI 8x 3 ^c- 0 - Acehbooks.org

28 S U M A T R A ,
coral powder is in particular places accumulated on the fhore in great
quantities, and appears, when not clofely infpedted, like a fine white
fand.
Surf. The Surf (a word not to be found, I believe, in our dictionaries) is
ufed in India, and by navigators in general, to exprefs a peculiar fwell
and breaking of the fea upon the fhore; the phcenomena of which not
having been hitherto much adverted to by writers, I fhall be the more
eircumftantial in my defcription of.
The furf forms fometimes but a fingle range along the fhore. At
other times there is a fucceffion of two, three, four or more behind each
ether, extending perhaps half a mile out to fea. The number of ranges
is generally in proportion to the height and violence.
The furf begins to aflume its form at fome diftance from the place
where it breaks, gradually accumulating as it moves forward, till it gains
a height, in common, of fifteen to twenty feet, when it overhangs at top,
and falls like a cafcade, nearly perpendicular, involving itfelf as it defcends.
The noife made by the fall is prodigious, and during the ftillnefs
of the night, may be heard many miles up the country.
Though in the rifing and formation of the furf, the water feems to have
a quick progreffive motion towards the land, yet a light body on the
furface is not carried forward, but on the contrary, if the tide is ebbing,
will recede from the fhore ,• from which it would follow, that the motion
is only propagated in the water, like found in air, and not the mafs of
water protruded. A fimilar fpecies of motion is obferved on fhaking
at one end, a long cord held moderately flack ; which is exprefled by
the word, undulation. I have fometimes remarked however, that a body
which finks deep, and takes hold of the water, will move towards fhore
with the courfe of the furf, as is perceptible in a boat landing, which
fhoots fwiftly forward on the top of the fwell; though probably it is
aided