112 QUESTIONS ON THE 



31. What is Heat? 



32. What is meant by the term Caloric ? 



33. What effect do we produce on a heated body by 

 touching it, and what on a cold body ? 



34 . By what term are those bodies distinguished which 

 transmit caloric readily ? 



35. Which are the best and which the worst conduc- 

 tors of caloric ? 



36. Why does the quicksilver or alcohol rise in the 

 Thermometer in hot weather ? 



37. What do the thermometers contain which are used 

 in the higher latitudes ? 



38. What is the natural state of bodies ? 



39. What is meant by atomic motion ? 



40. Does water, when converted into ice, take up more 

 or less space than when in its fluid state ? 



41. At what angle do the crystals of frozen water 

 form? 



42. When water is converted into steam, what strik- 

 ing power does it acquire? 



43. What is the chief source or cause of caloric? 



44. Into how many kinds is caloric divided, which are 

 they, and explain them ? 



45. Which colour radiates heat most ? 



46. Which colour absorbs the rays of light, and which 

 reflects them most ? 



47. What would be the effect produced on a vessel 

 scratched, as it regards the radiation of heat ? 



48. What is it said that the cause which produces the 

 sensation of heat resembles ? 



4Q. What is the shape of those mirrors used to con- 

 centrate the sun's heat ? 



50. What eifect has a convex lens on the sun's heat ? 



51. What is the difference between a lens and a 



mirror 



52. By what means did Archimedes set fire to the 

 Roman fleet? 



53. In what ratio were the sun's rays condensed by 

 Mr. Parker's burning-glass ? 



54. What person, in the reign of Elizabeth, ignited 

 bodies by a combination of plane mirrors ? 





