SUMATRA, ^$ 
degree of hardnefs, it may cafily be cut with a knife or any iharp in- 
ftrument ; it Is not folublc in water, and makes no effervefcence with 
acids. Its component parts appear to be clay and fand bound together 
by a glutinous or foponacious naatter, and its color is either grey, brown 
or red, according to the nature of the earth, that prevails in its com- 
pofition. The red nappal has by much the fmalleft proportion of fand, 
and feems to i>offefe all the qualities of the fteatite or foap earth, found 
in Cornwall and other countries. The mountain Hone is a fpecies of gra- 
nite, for the moil part of a lightifli ilate colour* 
Where the encroachments of the Tea have under minded the land, the 
cliffs are left abntpt and naked, in fome places to a very confiderable Pcircfaaion. 
height* In thefc many curious foiEls are difcovered, fuch as petrified 
wood, and fea mcu^ *^ ,r«^u,to fom. Hvpothefes on this fubje^ft have 
been fo ably fupported and fo powerfully attacked, that I fhall not pre- 
fume to intrude myfelf in the lifts, I lhall only obferve, that being fo 
ftear the fea, many would hefitate to allow fuch difcoveries to be of any 
weight in proving a violent alteration to have taken place in the furface 
of the terraqueous globe ; whilft on the other hand it is unaccountable 
how, in the common courfe of natural events, fuch extraneous matter 
fliould come to be lodged in ftrata, at the height perhaps of fifty feet 
above the level of the water, and as many below the furface of the land. 
'Here are likewife found various fpecies of earths, which might be ap- 
pikd to valuable purpofes, as painters colours and other wife. The moft 
common are tin. j -iUw ^nd red, probably ochres, and the white, which 
anfwers the defcription of the mtknum of the ancients. 
There are a number of volcano mountains in this, as in almoft 
all the other iflands of the eaftern archipelago. They are called 
in the Malay language goomi^ appee, I have never heard of the 
lava flowing from them in fuch a quantity, as to caufe any damage ; 
but this may be owing to the thinnefs of population ^ which does not 
render itneceffary for the inhabitants to fettle in their neighbourhood. 
The only volcano I h^d an opportunity of obferving, opened ia the fide 
of 
1 
