SCIENCE IN ADULT EDUCATION 313 



of planets, appearances of comets, and similar aspects of the sky now 

 determined by a single law. Unnecessary to assume association of any 

 such events with occurrences and people on the earth, such as visitations of 

 plague, human iniquities, wars, etc. Sense of justice and civilising influence 

 which resulted from a knowledge of the existence and permanence of law in 

 Nature. 



Intellectual expansion brought about by new knowledge of celestial 

 bodies and the extent of the universe. 



Eclipses of the sun and what they reveal. Solar prominences and the 

 discovery of helium in them. Identification of helium on the earth and its 

 use in airships, etc. Sunspots and the solar cycle, and their effect upon 

 magnetic conditions and broadcasting. Relationship between the sunspot 

 period and levels of lakes in Central Africa. Search for direct connection 

 between solar conditions and terrestrial weather. 



The Milky Way or Galaxy ; Galileo's observations of its character ; 

 Milton's references to them. 



The Milky Way interpreted as the girdle of the stellar system : Sir 

 William Herschel's conclusions as to the structure of this system. Modern 

 views as to ' island universes ' or stellar systems, represented by spiral 

 nebulje, beyond the Milky Way. 



Origin of the solar system. Laplace's nebular hypothesis ; Tennyson's 

 accurate references to it ; objections to the theory and search by astronomers 

 for a substitute for it. Great interest now shown by intelligent public in 

 new conceptions of the nature and origin of the solar system and the stellar 

 universe. 



Sir Richard Gregory. 



Chemistry and Citizenship. 



Fire. — The discovery of fire and its influence on civilisation. Ancient 

 and modern methods of producing fire. The chemical nature of burning. 

 Accidental fires. Chemical fire extinguishers. Fire-proofing of fabrics. 



Chemistry and Plant Growth. — Origin and nature of soil. Fertile and 

 barren soils. The elements needed for plant growth. How the plant 

 obtains its food from the air and from the soil. Soil exhaustion. Natural 

 and artificial fertilisers. Micro-organisms in the soil. 



Food. — Requirements of the body for energy and maintenance of tissues, 

 proteins, fats, carbohydrates, salts, water, vitamins. Importance of special 

 elements, e.g. iodine. Effects of cooking, refrigerating, canning, chemical 

 preservatives. 



Coal and Coal Products. — Origin and varieties of coal, coal distillation : 

 gas, coke, smokeless fuel, coal tar, hydrogenation of coal. Efficient burning 

 of coal. 



Petroleum. — Origin and nature. Petrol. Kerosene, Diesel oil, lubrica- 

 ting oil, greases, wax. Hydrogenation. ' Ethyl ' petrols. 



Textiles. — Nature of wool, silk, linen and cotton fibres. Artificial silk, 

 artificial wool. Mercerised cotton. Problems of wear and laundering. 



Rubber. — Origin and properties. Vulcanisation. Direct manufacture 

 from latex. Fillers and effect on strength, life, etc. Artificial rubber. 



Plastics. — Discovery, manufacture, properties, uses, etc., of synthetic resins. 



Metals and Alloys . (a) Ferrous. — Order of discovery of metals. Successive 

 methods for making iron. Discovery of steel. Properties of steel in 

 relation to composition and heat treatment. Rusting and its prevention. 



Metals and Alloys. (6) Non-Ferrous. — Copper, tin, brass, aluminium, 



