320 THIRD JOURNEY TO THE CAUCASUS. 



solutely diminished within historic times, which might 

 be concluded from many phenomena, or whether only 

 its distribution has become different, cannot as yet be 

 decided. 



The astonishingly large number of wooden prospect- 

 towers thirty to fifty feet high in the wholly flat region, 

 which afforded but the smallest prospect, is explained 

 by the circumstance, that the inhabitants in the worst 

 fever- season pass the nights in these towers to escape 

 the fever. 



A peculiar spectacle was afforded towards the 

 end of the journey by a whole town of similar wooden 

 towers, standing much higher still, apparently close 

 to one another, which crowned the summit of a near 

 mountain -range. More exact observation through a 

 telescope revealed that they were high boring-towers, 

 such as are wont to be erected for deep borings. This 

 was the district of the famous naphtha wells. Thence 

 the oil is conveyed for refining through numerous 

 conduits to the neighbouring "black town" of Baku 

 or rather to its newer part, which contains the 

 numerous petroleum distilleries. It is remarkable that 

 borings in the closest proximity, sometimes more than 

 a thousand feet deep, often yield altogether different 

 results. Frequently, on reaching the petroleum stratum, 

 a fountain arises, from which the naphtha spurts up to 

 a height exceeding a hundred feet. A hollow is then 

 quickly made in the neighbouring soil, to collect the 

 gushing naphtha. The yield of the well however soon 

 diminishes. After a few weeks it is wont no longer 



