YENANGYOUNG. 99 



the instances here mentioned rendered it almost beyond doubt that 

 the wells are distributed along a zig-zag line, which follows a certain 

 system. 



The cue thus given has been followed up, and when not proved by 

 the actual situation of a well, the direction of the lines was supposed 

 to run parallel to another one already proved. In this way the map, 

 plate XI, was constructed, and it is at once clear, that there must be 

 a certain rule with regard to the situation of wells producing more 

 oil than others. It will be seen that in thus connecting the wells 

 of each class, by lines, each class is situated within a certain 

 well defined area to the total exclusion of all the wells of 

 other classes. We notice that the richest wells form a rather 

 narrow belt in the centre, this is surrounded by a broader belt of 

 indifferent wells, and the latter is again surrounded by a belt of 

 wells yielding only a small quantity of oil. 



Before proceeding any further I must at once explain that I do 

 not by any means believe that the lines as laid down on this map 

 represent actual boundary lines, the strip of rich wells may be 

 a little broader than depicted, but it is clear that it cannot extend 

 beyond the line connecting the indifferent wells, and the same of 

 course applies to the latter with regard to the poor wells ; 

 they cannot possibly extend beyond this line. Though it may 

 be quite possible that, with the advance of our knowledge of the 

 structure of the oil field, the lines will be perhaps somewhat modi- 

 fied, the main features will probably remain. 



The belts, it will be seen, run in a very curious zig-zag manner, 

 and it is quite evident that whenever we find an indentation on the 

 one side, it corresponds to a projection at the opposite one. 



Another feature is also remarkable ; it seems that the Kodoung 

 petroliferous area is separated from the Twingon field by a band 

 containing only a small quantity of oil, and that the tail end, so to 

 speak, of the Twingon belt indents the Kodoung belt just at its 

 north-eastern corner, as apparently indicated by the indifferent wells 



H 2 ( I45 ) 



