GASKELL 



2404 



GASOLINE 



accomplished by having a piston fit into the 

 cylinder. When the gas in the chamber is 

 exploded the piston is forced outward. This 

 outward motion of the piston is controlled by 

 a crank shaft. The crank shaft not only deter- 

 mines the distance the piston goes, but is it- 

 self rotated by the force of the piston's mo- 

 tion, and in turn draws the piston back to 

 its original position. 



Meanwhile, the condition in the cylinder de- 

 serves attention. When the gas in the com- 

 pression chamber is exploded, by means of an 

 electric spark, the combustion instantaneously 

 raises the temperature of the gas, a temperature 

 of 1500 C., or over 2700 F., being not unusual. 

 This increase in temperature is accompanied 

 by a tremendous expansion in volume. As the 

 gas expands, it drives forward the piston with 

 a pressure which may be several hundred 

 pounds to the square inch. The burnt gases 

 then escape through valves in the compression 

 chamber, and a new supply of gas is admitted. 

 When the piston returns, as explained above, 

 by the motion of the crank shaft, it com- 

 presses the new supply of gas, and the entire 

 operation is repeated. In a two-cycle engine 

 there is one explosion for two strokes, forward 

 and backward, of the piston, or for each revo- 

 lution of the crank shaft. In a four-cycle en- 

 gine there is one explosion for four strokes or 

 two revolutions. 



How Ignition or Explosion Is Produced. In 

 practically all modern gas engines ignition is 

 produced by means of an electric spark. The 

 current may come from a magneto or dynamo, 

 or from a storage or other variety of battery. 

 The electric spark is made to jump between 

 terminals which are fixed in the mixture to be 

 ignited. These terminals are usually mounted 

 in a spark-plug, which insulates one or both of 

 the terminals, and is so constructed that it 

 can be easily removed and replaced if broken. 



Capacity of Gas Engines. The largest single 

 gas engine in existence furnishes 2,000 horse 

 power in its four cylinders. Greater power 

 than this can be obtained by a combination 

 of additional units. The smallest gas engine 

 made has a capacity of only a fraction of a 

 single horse power. W.F.Z. 



Consult Wimperis's Primer of the Internal Com- 

 bustion Engine; Carpenter and Diederichs's In- 

 ternal Combustion Engine. 



GAS'KELL, ELIZABETH CLEGHORN (1810- 

 1865), a British novelist, whose books possess 

 an irresistible quality of charm, was born in 

 London in 1810. Her father had been a Uni- 



tarian minister, but gave up the calling to ac- 

 cept the position of keeper of records of the 

 Treasury in London. Her mother died shortly 

 after her birth, and the girl's childhood was 

 spent with an aunt in Knutsford, near Man- 

 chester. Knutsford is Cranford, and the vol- 

 ume bearing that name attests the author's 

 knowledge of the spirit of the place. She was 

 married to William Gaskell, a minister of 

 Manchester, when she was twenty-two, at 

 which time she was noted for her remarkable 

 beauty. Twelve years after her marriage the 

 death of her only boy turned Mrs. Gaskell's 

 thoughts to writing as an escape from sorrow. 



Her first novel, Mary Barton, was published 

 in 1848. The book had as its background the 

 unending strife between employer and em- 

 ployed. Its practical result was to help create 

 a better atmosphere, which meant ultimate 

 improvement in social conditions. Charles 

 Dickens was so pleased with the book that he 

 invited Mrs. Gaskell to cooperate with him in 

 Household Words, and to this magazine she 

 contributed a great many stories and sketches. 

 Among the latter, appearing from 1851 to 1853, 

 were the separate sketches which became the 

 chapters of Cranford, and which were published 

 in book form in 1853. It is regarded as a 

 classic, and stands higher in popular favor 

 to-day than any other work of Mrs. Gaskell. 

 Cranford is a chronicle of bright incidents 

 which reveal the people and embody the spirit 

 of a little town. It has a sunny humor, a 

 tranquil common sense and a humanity that 

 ranges from laughter to true pathos. 



In the short period between 1860 and the 

 year of her death Mrs. Gaskell produced three 

 other stories, Sylvia's Lovers, Cousin Phillis, 

 and an unfinished novel, Wives and Daughters, 

 published in two volumes in 1866. M.R.T. 



GASOLINE, gas o leen' , a highly inflammable 

 liquid which looks like water, but is lighter 

 and has a characteristic odor. Gasoline is one 

 of the products of petroleum (which see). It 

 is an exceedingly volatile liquid; that is, it 

 evaporates rapidly on exposure to air. It can- 

 not be kept in wooden barrels for any length 

 of time, for no matter how cold the weather, 

 it forces its way through wood. It must, 

 therefore, be placed in metal receptacles, and 

 the law requires that tanks containing it must 

 be kept underground. 



Uses. On account of the high explosive 

 quality of suitable mixtures of gasoline gas 

 with air, gasoline can be employed so advan- 

 tageously that it has become within recent 



