Jt!NE 1, 1898.] 



KNOWLEDGE. 



125 



hundred feet high, and then fell, forming, together with 

 the sand which it had carried up from the well, banks of 

 sand enclosing lakes of oil, much of which ran out in a 

 broad channel towards the sea. When, after about three 

 months, the well was brought under control and capped, 

 it was estimated to have yielded between two hundred and 

 twenty thoufand and five hundred thousand ton.'< of petro- 

 leum, most of which was wasted. Mr. P. Stevens, our 

 Consul at Baku, states that early in 1893 a well drilled 

 in the district yielded oil at the rate of seventeen thousand 

 seven hundred and forty-two tons daily, an amount far in 

 excess of that of the Droojba well. Most of this oil also 

 was wasted. 



Oil is mainly obtained from the districts already men- 

 tioned ; still, petroleum occurs in many countries and in 



Derricks in the Oilfield of Bradford. 



most of the strata comprised between the older Laurentian 

 rocks and the newer members of the Tertiaries. In the 

 United States the principal deposits lie in Pennsylvania 

 and New York (which are generally taken as forming 

 one field), and in Western Virginia, Ohio, and Indiana. 

 Notwithstanding the new fields that are being opened up, 

 the amount of unprospected country is now by no means 

 large ; whereas, in Russia, enormous areas of proved 

 oil territory, as well as still larger tracts of presumably 

 oil-bearing land, are lying fallow because the small areas 

 actually imder the drill are capable of more than supplying 

 the immediate demand. In Grosnia, and in the Kouban 

 and the Crimea, as well as on the Apsheron peninsula, of 

 which the oil district of Baku forms a small part, we have, 

 for instance, proved tracts of land the output of which is 

 likely to be enormous when the exigences of the market 

 call for their development. 

 Petroleum occurs in commercially workable quantities in 



Canada, Gahcia, Boumania, India, Java, and Sumatra ; also 

 in Japan, China, Peru, Germany, and many other countries ; 

 and it has been found in several parts of England, though, 

 not in sufficient quantity to admit of profitable working. 



Taking the oils of America and Kussia as the most 

 important and typical, it is interesting to consider the 

 different geological conditions under which they occur. 

 The American oil is found in strata of the Silurian and 

 Carboniferous epochs, and belongs to what is known as 

 the " paraffin " series of compounds ; while that of Russia 

 may be referred to the Eocene and Miocene strata of the 

 newer Tertiary series, and consists of compounds of the 

 " benzene " family. 



The American oil yields on distillation about seventy 

 per cent, of kerosene oil suitable for ordinary lamps, 

 together with lighter products form- 

 ing the various petroleum "spirits," 

 heavier oils used in gas manufacture, 

 lubricating oils, paraffin wax, vase- 

 line, and residuum utilized as liquid 

 fuel. The Russian oil, on the other 

 band, yields less than half as much 

 kerosene and light distillation pro- 

 ducts as does the American oil, and 

 practically no paraffin, but it gives a 

 higher and better yield of lubricating 

 oil and a larger proportion of 

 residuum, which, under the name 

 " astatki," is used as fuel more in 

 Russia than in any other country. 



In America, as in all other 

 countries, the earlier developments 

 were due to the appearance of 

 petroleum on the surface of the land, 

 4^*, S^^E^St or tD its occurrence in wells sunk for 

 S;?*' nSi^^E^HH water or brine ; but now the oil wells 

 are very deep, those in the deepest 

 drilled district — the Washington dis- 

 trict of Western Virginia — averaging 

 two thousand four hundred feet. The 

 oil occurs mainly in the interstices 

 separating the grains of sandstones, 

 or between the crystals of a dolomitic 

 rock ; and experience has shown that 

 it is necessary to raise the oil without 

 regard to market requirements, or 

 the whole may be pumped up through 

 the wells of the neighbouring lease- 

 holders, a condition of things which 

 has led to a common practice of 

 drilling round the boundary of the 

 holding before commencing operations elsewhere. 



In Russia, however, the conditions are different ; the 

 oO is usually found at comparatively shallow depths, often 

 not more than one-fourth of the depth of the American wells. 

 A loose sand, consisting of independent grains, comes up 

 with the oil, and these grains of sand are a cause of serious 

 trouble in the flowing wells on account of their cutting 

 action on the caps with which the drillers endeavour to 

 close the top of the well-casing to control the outflow. In 

 the case of some of these tiowing wells, the blast of sand 

 has been known to cut through several thick steel caps 

 before the flow could be stopped. The strata in which the 

 oil occurs are also so disturbed as to practically constitute 

 a large number of independent oil reservoirs, so that closely 

 contiguous wells are found to be practically independent 

 of each other, and there is no necessity for raising the oil 

 until required. 



Had space permitted, it would have been interesting to 



