MATTER FORMED OF SMALL PARTICLES 115 



15. Make the following observations and give explanations in each 

 case : (a) That mercury will not run through a fine gauze or cambric, 

 while water does so. (#) That a plate, suspended by beeswax and 

 twine from the end of a balance so that its lower surface is completely 

 in contact with the surface of some water, will require a considerable 

 mass to be placed in the other pan of the balance, before it is detached 

 from the surface of the water. (<?) That a larger mass is required in 

 the case of mercury, (d) That a large globule of oil may be obtained 

 by placing it in a mixture of water and alcohol of its own density. 



16. How is evaporation distinguished from ebullition? Describe 

 what probably takes place in each case. 



17. What evidence is there that the particles of a gas, liquid, and 

 even a solid, are in motion at ordinary temperatures ? 



18. Find out what alterations of volume take place when a given 

 quantity of water, and also of alcohol, takes increasing quantities of 

 various salts into solution. 



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