1879.] Native Bitumens and the Pitch Lake of Trinidad. 243 
rain-water collects. These anastomose and divide most curiously, 
forming one connected system, and dividing the pitch into 
numerous flat-topped or slightly convex areas or islands which > 
are usually of quite irregular outline, though sometimes nearly 
circular, and from ten to one hundred feet in diameter. A piece 
of marbled paper would make an excellent map of the lake. 
The sides of the channels are always convex, presenting curves 
of great regularity and beauty; and where three or four chan- 
nels meet, a star-shaped depression is formed. Canon Kingsley! 
says, “ Conceive a crowd of mushrooms, of all shapes, from ten to 
fifty feet across, close together side by side, their tops being kept 
at exactly the same level, their rounded rims squeezed tight 
against each other ; then conceive water poured on them so as to 
fill the parting seams. Thus would each mushroom represent, 
tolerably weil, one of the innumerable flat asphalt bosses which 
seem to have sprung up, each from a separate center, while the 
parting seams would be of much the same shape as those in the 
asphalt, broad and shallow atop, and rolling downward in a 
smooth curve till they are, at bottom, mere cracks from two to 
ten feet deep. Whether these cracks actually close up below and 
the two contiguous masses of pitch become one, cannot be seen. 
As far as the eye goes down they are two, though pressed close to 
each other,” the hard exteriors of the masses preventing them from 
coalescing. 
The water filling the channels is clear, pure rainwater, and con- 
tains numbers of small fishes, water beetles and other aquatic 
animals. It has been observed escaping from the canals at eight 
nearly equidistant points on the circumference of the lake. 
Several hypotheses have been proposed to account for the 
peculiar structure of the lake. Mr. Manross says, “ The chan- 
nels are produced and maintained by the following singular pro- 
cess: Each of the many hundred areas into which the lake is 
divided possesses an independent revolving motion in this wise: 
In the center of the area the pitch is constantly rising up ez masse, 
displacing that which previously occupied the center, and forcing 
it towards the circumference. The surface becomes covered with 
concentric wrinkles and the interior structure somewhat lami- 
nated. Where the edge of such an expanding area meets that of 
the adjoining one the pitch rolls under to be thrown up again in 
the center at some future period. It is difficult to conceive of a 
1 At Last: A Christmas in the West Indies. 3 
