SUMATRA- 
coral powder is in particular places accumulated on the ihore in great 
quantities, and appears, when not clofely infpcdedj like a fine white 
fand. 
The Surf (a word not to be found, I believe, in our di6:ionaries) is 
ufed in India^ and by navigators in general, to exprefs a peculiar fwell 
and breaking of the fea upon the fliore; the phoenomena of which not 
having been hitherto much adverted to by writers, I fliall be the more 
circumftantial in my defcription of* 
The furf forms fometimes but a fmgle range along the fliore. At 
other times there is a fucceiEon of two, three, four or more behind each 
other, extending perhaps half a mile out to fea. The number of ranges 
i# g*>n<='rallv in proDorcion tn t^^'" ^r^^u'^*' ^-;*>ionoc. 
The furf begins to aflfume its form at fome di fiance 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, 
anci falls like a cafcade, nearly perpendicular, involving itfelf as it de- 
■fcends. The noife made by the fall is prodigious, and during the ftill- 
nefs of the night, may be heard many miles up the country. 
Though in thcrifing and formation of the furf, the water feems to have 
a quick progrefTive motion towards the land, yet a light body on the 
furfacc is not carried fonvard. H^t i-v^ **;*t*ftijf, ii the tide is ebbing, 
will recede from the fhore ,* from which it would /ollow, that the motion 
is only propagated in the water, like found in air, and not the mafs of 
water protruded* A fimllar l|)ccies of motion is obferved on fhaking 
at one end, a long cord held moderately flack ; which is expreffed by 
the word, undulation, I have fometimes remarked however, that a body 
which finks deep, and takes hold of the water, will move towards fliore 
with the courfe of the furf, as is perceptible in a boat landing, which 
flioots fwiftly forward on the top of the fwell ^ though probably it is 
aided 
