ASI'lIALTUM FOR A MODE US STREET. 



231 



parent! y has its source in subterranean springs. The areas of pitch 

 arc of considerable extent, highest in the middle, but still nearly level 

 and gently sloping on all sides to the precipitous edges of the water 

 areas. These areas are being continually elevated in the center by rising 

 gas, which, forcing up the center in huge bubbles, cause a continual 

 ebullition of the plastic mass and a gradual transference of the material 

 from the center towards the circumference, so that trunks ami branches 

 of trees submerged in the pitch come to the surface, rise, and after 

 assuming a perpendicular position, are in time again submerged to an 

 unknown depth. From the escaping gas the whole central portion of 

 the lake is maintained in a constant motion that prevents vegetation 



Fig. \. Tramway and Trucks on PrTCH Lake. 



from taking root, and leaves the surface of the areas of pitch bare 

 and of a blue-black color. 



When the pitch is dug, a negro will drive a long, slender pick to the 

 eye at a single blow, and, by using the handle as a lever, will break out 

 a flake of pitch larger than he can lift. From less than an inch below 

 the surface the pitch is of a brown color, saturated with water and filled 

 with bubbles of gas. A broken mass will soon dry on the surface and 

 melt, forming a pellicle that will enclose the wet mass for years and 

 prevent the escape of the water. In this wet and porous condition it is 

 calied "cheese pitch.' It is not sticky at all, as the water can be squeezed 

 from it in the hand, as if it were a sponge. 



Formerly the large lumps of this cheese pitch, as it was broken out, 

 were transported to the beach in carts, but about 1893-4 a wharf was 



