CHAPTER I.

13. What is said of the distinction between matter and spirit? What of Bishop Berkeley's ideas? What of Hume's?

14. What is the origin of the word spirit? What is the relation of the senses to the spirit? What is said of the effects of matter on the senses? What are the forms of matter?

15. Illustrate the difference between elastic and non-elastic fluids. What is said of the union of the particles of a solid? Give the difference noted between different solids. How does a liquid differ from a solid? Give particularly what is said of water.

16. What is said of the particles of gaseous substances? What of the atmosphere? What of the vapor in it? What is said of the entering of liquids and gases into interstices? What of the mingling of gases with liquids? Give the illustration in regard to fishes.

17. What is said of the solution of solids in liquids? What of the evaporation of water in the air? Illustrate the influence of heat on the forms of matter. What is said of the thermometer? What of mercury, water, and iron in relation to the liquid state? What is said of our knowledge of matter?

18. What was the supposition of Newton about the composition of matter? What is said of the changes of matter? What are the imponderable agents, and why are they so called?