Calendar: 1877-1878 Page 618

6 CLOTHWOBKERS' SCIENCE EXHIBITION substance depend Describe method of determining the velocity of sound in metal wire 10 Explain how the refraction of light by plane surface is accounted for by the Wave theory Explain how the appearance of stick immersed obliquely in water agrees with the law of refraction 11 Shew how to find tbe index of refraction of any solid or liquid prism Explain how it is possible by means of prisms to obtain deviition without dispersion 12 Describe and explain the appearance presented when cnnvexlens is placed in contact with plane surface of glass and beam of light is reflected from their surfaces near the point of contact -Snorganir Cijrmtstn Mention the ingredients of gunpowder Why is it classed among mechanical mixtures and not among chemical compounds What are the gases present in atmospheric air Describe simple method or their detection Describe and explain by chemical equation process by which pure hydrogen may be obtained If 12 grammes of carbon were completely consumed by oxygen gas what new substance would be produced and what would be its weight Whence is nitric acid obtained Mention some of its uses Give chemical explanation of the explosions so frequent in coal-mines How would you distinguish from each other the metals tin lead and zinc solution gives with hydrosulphuric acid black precipi- tate with ammonia white precipitate with potash yellow precipitate name the metal which it contains VI -Zoologp Define an animal in contradistinction to vegetable Give an account of the external conformation of the