182 REVIEW. 



19. Can you devise a plan by which an ordinary mercurial barom 

 eter may be used to measure the rarefaction secured by an air-pump ? 



20. (a.) Give the laws of liquid pressure, and (&. ) find the pressure 

 on one side of a cistern filled with water, 5 feet square and 12 feet 

 high ? 



21. (a.) What is specific gravity? (6.) What the standard for 

 liquids and solids? (c.) How is the sp. gr. of solids found? 



22. Calculate the atmospheric pressure upon a man having a body 

 surface of 16,000 sq. cm. 



23. What is the upward pull of a balloon of 1,000 cu. m., when 

 filled with gas half as heavy as air, its own weight being 25 Kg. ? 



24. (a.) State Archimedes' principle. (&.) How may it be experi- 

 mentally verified ? (c.) In finding specific gravity, what is always 

 the dividend and what is always the divisor ? (d.) A specific gravity 

 bulb weighs 88 g. in air, 28 g. in water, and 20 g. in an acid. Find 

 the sp. gr. of the acid. 



25. (a.) Describe an overshot water -wheel, and (&,) give a drawing. 



26. (a.) Define the three kinds of equilibrium, (b.) Where is the 

 centre of gravity in a ring? (c.) Why are lamps, clocks, etc., pro- 

 vided with heavy bases ? 



27. Find the weight in sulphuric acid (sp. gr. 1.75) of a piece of 

 lead weighing 150 g., and having a sp. gr. of 11. 



28. A pendulum 1 meter long makes 40 oscillations in a given 

 time ; how long must a pendulum be to make 60 oscillations in the 

 same time and at th'e same place ? 



29. (a.) Give Mariotte's law. (&.) How high could a fluid having 

 a sp. gr. of 1.35 be raised in a common pump when the barometer 

 stands at 29.5 inches ? 



30. Represent, by drawings in section, the essential parts of (a.) 

 an air-pump, (&.) a lifting-pump, and (c.) a force-pump, (d.) Why 

 does the water rise in the suction pipe of a lifting-pump? (c.) 

 What is the immediate force that throws water in a steady stream 

 from a force-pump ? 



81. Water flows from an orifice 25 feet below the surface of the 

 water, and 144.72 feet above the level ground. Find the range of 

 the jet. 



32. State briefly, by diagram or otherwise, the distinguishing 

 features of solid, liquid and aeriform bodies. 



