The Atmosphere in relation to Malaria. 221 



fact, (although this inference might be considered premature) 

 proceeds to speculate upon the nature of the compound, of 

 which the hydrogen forms a constituent. He considers it 

 to be in union with carbon, forming carburetted hydrogen. 



Saussure inferred from his experiments that an inflam- 

 mable gas existed in the atmosphere with a base of carbon. 

 Boussingault ascribes its origin to exhalation from the 

 earth, in the decomposition of vegetable matter, and also 

 from mineral sources. 



Near the falls of Niagara there is a fertile source of it in 

 the Burning Spring. In Italy and Sicily it occurs in abun- 

 dance, and in China, about Kratnig-fou there are within 

 50 square leagues, no less than 10,000 salt pits, from all of 

 which, inflammable gas is emitted. Near the town of 

 Kioung-tcheou, there is a pit of 5^ feet deep and 16 in dia- 

 meter. The gas proceeding from this pit, when set on fire, 

 forms such a blaze that the whole country is illuminated 

 during the night to a great extent. Near Bakow, likewise, 

 according to Imbert, there are some extensive sources. 

 Discharges of the same nature frequently occur in this 

 country. Dr. Thomas Thomson has described one, which 

 existed in the neighbourhood of Glasgow, where the gas 

 burst forth in different parts of a hill side. When examined, 

 it was found to contain only 12 percent, of common air. 



Article X. 



State of the Austrian and Hungarian Mines. By Messrs. 

 FoY, Harle, and Gruner.* 



The Tyrol contains very few mines which are now worked, 

 although the country is rich in copper and silver. 



The mines of Schwatz, on the Inn, are abandoned. 



At Kitzblibel, 1200 quintals f of copper are procured 

 annually from pyrites in veins in clay slate. 



The Tyrol produces only 35 marcs (22 troy lbs.) at Zell. 



The annual product of iron manufactured is 10,000 quints., 

 and of steel 2000. At Hall, there is a large saline deposit, 

 from which 200,000 quintals of salt are raised, at Is. 10|d. 

 per quintal, and sold at 10s. lOd. per quintal. Besides, 



• Ann. des Mines, Tom. V. + A quintal is equivalent to 109*81 lbs. Arord. 



