154 NOETLING: PETROLEUM IN BURMA. 



closely followed by oil with a specific gravity from o 1 9032 to 

 o- 8750. 



Turning to the specific gravity of petroleum derived from dif. 

 ferent depths, the figures apparently prove that the oil becomes 

 lighter with depth, as seen from the following table. The average 

 specific gravity of oil drawn from the 



1st oil sand (wells below 151 feet) j s . 0-9147=0-9209 at 6o° F. 



2nd „ ,, „ from 151 to 200 „ . 0-9279 = 0-9465 



3^ „ „ a „ 2oi to 250 „ . 0-8891=0-9011 



b „ 251 to 300 „ . 0-8766 = 0-8921 



c more than 300 „ . 0-8742 = 0-8858 



d „Kodoung wells ,, . 0-8712 = 08823 



Grand average of Yenangyoung oil . . 08917 = 0-9171 



However, in going through each of the tables, we find that there 

 are wide differences in the specific gravity of oil which apparently 

 comes from one and the same geological horizon. The explanation 

 is easy; in the pit wells the oil from the upper bed is not shut off 

 when the well is deepened, but is allowed to filter into the well, 

 where it mixes with the lighter oil of the deeper sand and the result 

 is that the oil from the deeper pit wells is in many cases a mixture 

 of oil coming from various sands, but still we can see that, whatever 

 may be the origin of the very heavy oils in the deeper wells, petro- 

 leum of lighter specific gravity predominates in them. 



In conclusion I may be allowed to say a few words on the prac- 

 tical importance of the specific gravity of the oil. Since immemorial 

 times the petroleum from Burma has been sold by weight ; the 

 standard being 100 viss, equal to 365lbs. The production 

 of the deep wells is, however, ascertained in a different way; the oil 

 is conducted into large iron tanks, the contents of which are daily 

 gauged by a measuring rod, and thus the volume, expressed in 

 gallons, attained. The weight is obtained in the usual way, but it 

 is of course quite clear that according to the specific gravity the most 

 varying figures will be obtained. A certain average specific gravity 

 will of course do for all practical purposes, but even that requires a 

 certain amount of correction. Let us for instance assume the 

 average specific gravity to be o' 8917 at the average temperature 

 ( 200 ) 



