112 THE POPULAR SCIENCE MONTHLY. 



said lake can be proved. All that meets the eye is a level plain of 

 pitch about three miles in circumference, dotted over with patches 

 of vegetation and bushes, and jdooIs of rain-water, wherein women 

 wash and bleach their linen, while men with pickaxes dig out large 

 fragments of hard, resinous pitch, which are carried off in carts, all on 

 the surface of the so-called lake. Though only about a hundred acres 

 of pitch are thus 'exposed to view, the deposit crops up at several 

 points five or six miles to the north and to the south, and appears to 

 be only covered by a thin layer of soil or sand. The lake lies about 

 eighty feet above the sea. As the place of the Pitch Lake, in these 

 notes on the world's oil-supply, may not be self-evident, I may vent- 

 ure to remind my readers that the definition of petroleum {petri 

 oleum, " rock-oil ") is " a native liquid bitumen," which is essentially 

 asphalt dissolved in naphtha. So perhaps we shall some day see the 

 people of Trinidad start their own oil-factories. (The neighboring 

 Isle of Barbadoes also contributes its quota to the world's supply of 

 bituminous asphalt.) 



There are numerous petroleum-wells actually within the town of 

 Columbia, and, though the oil is of inferior quality and not abundant, 

 the poor collect it in cloths, which absorb the oil, and are then wrung 

 out into jars, and thus they obtain suflicient to light their houses. So 

 long ago as 1824, samples of this " oil of Columbia" were sent to Eng- 

 land, France, and the United States, as a remarkable new discovery ; 

 but the secret of distillation had not then been discovered, and kerosene 

 and benzine were unknown products, so this South American oil failed 

 to attract attention. In like manner we learn that in remote ages the 

 citizens of Genoa obtained their oil-supply from the wells on the 

 banks of the Taro. And, in the days of Pliny, Sicilian lamps were 

 fed from the oil-springs of Agrigentum ; and long before the Chris- 

 tian era the old Romans knew how to turn to account the oil-wells of 

 Zante. Yet no systematic working of any of these wells seems tO 

 have been attempted. 



Petroleum in some of its varied forms has long been known to ex- 

 ist in many different parts of Europe. In Galicia, Moldavia, and Rou- 

 mania, it is found in a semi-solidified form, which led to its being named 

 mineral fat or tallow — as in the so-called " tallow-wells." The ozo- 

 kerite or earth-wax of Galicia is found in great abundance, and of so 

 pure a quality as quite to take the place of beeswax in the manu- 

 facture of candles, etc. A considerable number of the population are 

 employed in mining for it, and also in working the industry in all its 

 branches. 



So far back as 1873, the annual return of burning-oil and paraffine 

 was valued at a sum equal to £500,000. This was chiefly obtained 

 from the Boryslaw district. 



In 1879 an American oil-refiner from Ohio determined to com- 

 mence work in Galicia on more scientific principles than any hitherto 



