GAS 



2402 



GASCONY 



APPARATUS FOR THE MANUFACTURE OF COAL GAS 



(a) Furnace; (6) retorts containing coal; (c) hydraulic main ; (d) condenser; (e) exhauster; (/) 

 scrubber; (g) purifier; (h) pipe leading to storage tank. 



only exit from the retorts. Gas at this stage 

 of its manufacture contains many impurities, 

 such as tar, sulphur, ammonia, carbon dioxide 

 and water vapor. The rest of the process is 

 largely one of purification. 



The gas leaves the retort and passes to a 

 large U-shaped pipe containing water. In pass- 

 ing through the water, it is freed of much of 

 its tar and ammonia. It is next forced by a 

 rotary pump into a tar extractor, where more 

 tar is removed at a temperature of about 100 

 F. The gas then passes to what is called the 

 condenser. The condenser is built something 

 like a tubular boiler; the gas passes through 

 a set of tubes in one direction while water 

 flows in the opposite direction outside the 

 tubes. The gas is then forced by the ex- 

 hauster (see diagram above) into contact in 

 the scrubber with water in a cylinder contain- 

 ing coke, gratings of boards or other porous 

 material. In the scrubber, more tar and am- 

 monia are washed out, and the gas is then 

 ready for the purifier. Here it passes through 

 layers of lime or of oxide of iron, and loses 

 any sulphur which it may contain. After this 

 process it is ready for use, and is stored in 

 huge tanks. 



Water Gas. Water gas, which is now used 

 in many cities, is made by passing steam over 

 red-hot coke or anthracite (hard coal). This 

 gas consists of hydrogen and carbon monoxide. 

 It burns with a very hot blue flame. In order 

 to render it useful for illuminating purposes, 

 it must be "enriched" with gases that burn with 

 a yellow flame. Frequently it is mixed with 

 coal gas. Sometimes it is enriched by adding 

 volatile liquids derived from coal or from 

 petroleum. On account of the large proportion 

 of carbon monoxide it contains, water gas is 



extremely poisonous, much more poisonous 

 than coal gas. 



Other Gases. Other illuminating gases are 

 acetylene (which see) ; Pintsch, or oil, gas, 

 made from petroleum, and used in lighting 

 railway cars; Blau gas, also made from petro- 

 leum; and gasoline gas, made by vaporizing 

 gasoline in a current of air. J.F.S. 



GAS CLOUDS, in warfare, are designed to 

 render the enemy helpless before an attack. 

 In April, 1915, Canadian and French troops in 

 the War of the Nations were surprised to see 

 a heavy, greenish cloud creeping toward them 

 along the ground at the rate of a few hundred 

 feet a minute. From its effects the cloud is 

 thought to have been composed of chlorine 

 gas, of which a very small quantity produces 

 a painful asphyxiation. Reference to the arti- 

 cle CHLORINE will show that this gas is well 

 suited to such a purpose, first, because of its 

 heaviness; second, because it may be trans- 

 ported to the trenches in liquid form, and, 

 third, because it is cheap. A satisfactory de- 

 fense against gas clouds was found in cotton 

 masks saturated with an alkali solution to 

 absorb the chlorine. See WAR OF THE NA- 

 TIONS. 



GASCONY, gas'koni, an old province of 

 France, north of the Pyrenees Mountains. It 

 took its name from the Vascones, who crossed 

 the mountains from Spain in the sixth cen- 

 tury. They long maintained independence, 

 but were finally subdued and ruled over by 

 Frankish dukes. Gascony was the scene of 

 many struggles between the French and Eng- 

 lish, who were at last driven out as a result 

 of the victories of Joan of Arc. The Gascons 

 were faithful and brave but much given to 

 boasting, whence comes the word gasconade t 



