36 PASCOE: GEOLOGICAL NOTES ON MESOPOTAMIA. 



but the amount of hydrogen sulphide evolved is very large. It 

 is not a difficult matter to oxidise H 2 S to S0 2 and ultimately to 

 H 2 S0 4 , and I think the occurrence is worth the attention of a 

 sulphuric acid expert. The supply may be variable, but the evolu- 

 tion has existed for some time and there is no reason why it should 

 not persist for many more years. The risks and difficulties to be 

 faced seem to be : — 



(i) The Tigris may attempt to revert to its old course. 

 (ii) The supply may vary with the season of the year. 

 (Hi) The supply may be altogether capricious. 

 (iv) The supply may be affected by any boring for oil in the 

 immediate neighbourhood. 



(i) could be controlled without much difficulty. With regard 

 to (Hi), the oldest inhabitants of a Kurdish village not far distant 

 assert that the phenomenon has existed ever since they can remember 

 and has been known for at least 100 years, so that the chances of 

 the evolution continuing indefinitely are good, provided contin- 

 gency No. (iv) does not interfere with it. The gas could be collected 

 by building a gas-tight dome over the " live " area of the stream 

 with a pipe leading off. Oxidation would soon destroy the smell. 



Two or three types of sulphuretted hydrogen burners are in 

 modern use for the manufacture of sulphuric acid, and all of them 

 of simple structure. One consists of a brick chamber with " baf- 

 fling-walls," into which the gas is admitted by a cast-iron pipe, the 

 rate being controlled by an inlet valve. Air for the combustion of 

 the gas is introduced partly by an annular aperture round the point 

 of ingress of the cast-iron pipe, and partly by a separate regulatable 

 aperture in the brick chamber. The heat produced is not only 

 enough to prevent the flame of the burning sulphuretted hydrogen 

 from being extinguished, but may also be used in concentrating the 

 final product. The process is perfectly continuous and uniform 

 and the consumption of nitre reduced in consequence. A different 

 fonn of burner furnished with shelves is described by E. Lombard. 1 

 If a complete sulphuric acid plant is thought unfeasible in the present 

 state of the country, large quantities of free sulphur could be obtained 

 by burning the sulphuretted hydrogen in a limited supply of air, 

 ■or by passing sulphur di-oxide into the stream. Sulphur di-oxide 



1 Monti. Sclent., 1889, p. 1231. 



