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verge. Its colour, and even the surface, presents, at first, the aspect 
of a lake of water. But Mr. Anderson imagines it obtained the ap- 
pellation of lake, when seen in the hot and dry weather ; at which 
time its surface, to the depth of an inch, is liquid j and then, from its 
cohesive quality, it cannot be walked on. 
It is of a circular form, and above three miles in circumference, 
appearing at first a plain as smooth as glass ; excepting some small 
clumps of shrubs and dwarf trees, that have taken possession of 
some spots of it; but, on a nearer view, it is discovered to be 
divided into areoloe of dilferent sizes and shapes ; the chasms or divi- 
sions anastamosing, through every part of it. The surfaces of the 
areolce are perfectly horizontal and smooth ; the margins are undu- 
lated, and each undulation is enlarged to the bottom, till it joins 
the opposite. On the surface, the margin, or first undulation, is 
distinct from the opposite, from four to six feet ; and the same 
depth before they coalesce ; but where the angles of the areol<s op- 
pose, the chasms or ramifications are wider and deeper. When Mr. 
Anderson was there, these chasms were full of water : the whole 
forming one true horizontal plain, which rendered his investigation 
of it difficult and tedious; being necessitated to plunge into the 
water a great depth, in passing from one areolee to another. The 
truest idea that can be formed of its surface, would be from the 
areolce, and their ramifications, on the back of a turtle. Its more 
common consistence and appearance, is that of pit-coal ; but its 
colour is rather greyer. It breaks into small fragments, of a similar 
appearance, and glossy ; with a number of minute and shining par- 
ticles interspersed through its substance. It is very friable; and, 
when liquid, is of a jet black ; some parts of the surface are covered 
with a thin brittle scoriae, a little elevated. As to its depth, he 
could form no idea of it, for in no part could he find a substratum 
of any other substance. Its smell resembled that of pitch, and it 
was so hard, that no impression could be made on its surface without 
