1 62 On the Pilch Lake of the tdand of Trinidad. 



so as to be slippery ; the hardness or consistence was such 

 as to bear anv weiiiht ; and it%as not adhesive, though ft 

 partially received the impression of the foot; it bore ns 

 without anv iremulous motion whatever, and several head 

 of cattle -were browsing on it in perfect security. In the 

 dry season, however, the surface is much more yielding, and 

 must be in a state approaching to fluidity, as is shown by 

 pieces of recent wood and other substances bemg enveloped 

 in it. Even large branches of trees which were a foot above 

 the level, had in some way become enveloped in the bitu- 

 minous matter. The interstices or chasms are very nu- 

 merous, ramifying and joining in every direction, and in 

 the wet sea=on, being filled with water, present the only 

 obstacle to walking over the surface : these cavities are 

 generally deep in proportion to their width, some being 

 only a few inches in depth, others several feet, and many 

 almost unfathomable: the water in them is good, and 

 uncontaminated by the pitch ; the people of the neigh- 

 bourhood derive their supply from this source, and refresh 

 themselves by bathing in it; fish are caught in it, and par- 

 ticularly a very good species of mullet. The arrangement 

 of the chasms is yery singular : the sides, which of course 

 are Ibrmed of the pitch, are invariably shelving from the 

 surface, so as nearly to meet at the bottom, but then they 

 bulge out towards each other with a considerable degree of 

 convexity. This may be supposed to arise from the ten- 

 dency in the pitch slowly to coalesce, whenever softened 

 by the intensity of the sun's rays. These crevices are known 

 occasionally to close up entirely, and we saw many marks 

 or scams from this cause. How these crevices originate it 

 may not be so easy to explain. One of our parly suggested 

 ,that the whole mass of pitch might be supported by the 

 water which made its way through accidental rents ; but in 

 the solid state it is of greater specific gravity than water, for 

 several bits thrown into one of the pools immediately sank*. 

 The lake (I call it so, because I think the common name 

 appropriate enough) contains many islets covered with long 

 grass and shrubs, which are the haunts of birds of the most 

 exquisite plumage, as the pools arc of snipe and pinyer. 

 Alligators are also said to abound here; but it was not our 



* Pieces of asplialtum are, I believe, frequently found floating on the Dead 

 Sea in Palestine ;biit tlu's arises piobrfblv tVom tl;e extraordinary specific gra- 

 vity of the waters of that lake, which i)r Marcet found to be \-'2\l. Mr. 

 Hatchett states the specific gravity of ordinary asphaltuni to vary from 1'023 

 to 1'1C5, but in two varieties of that of Trinidad it was as great as 1-S36 and 

 1'744, which led Mr. Hatchett to form a conjecture which 1 shall afterward* 

 notice. 



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