34. What is the length of a second pendulum in New York? Art. 55.

35. Describe a metronome. Art. 56.

PRINCIPLES OF MOLECULAR ACTION.

1. Define molecular forces. How divided? Art. 57.

2. Explain the effects of compressing and stretching bodies. Art. 57.

3. Define Cohesion.

Art. 58, 59.

Adhesion. Give examples of each.

4. Give example and explain the phenomena of Capillarity. Art. 60.

5. Give examples and illustrate the principles of Absorption and Imbibition. Art. 62, 63.

6. What principle is involved in the anecdote Pope Sixtus Quintus? Art. 63.

7. What effect will wetting ropes have on their length? Art. 63.

8. What is Tenacity? What bodies are most tenacious? Art. 64.

9. What is the form of greatest strength? Art. 64.

10. Define Hardness and Ductility. Malleability. Art. 65, 66, 67.

MECHANICS OF LIQUIDS.

1. Define Hydrostatics. Hydronamics. Art. 68, 69.

2. Say what you can concerning the properties of Liquids. Art. 69.

3. What is the principle of Pascal? Art. 70

4. State and explain the law in regard to the pressure of liquids. Art. 71.

5. How is the lateral pressure demonstrated?

Art. 72.

6. Explain the upward pressure of liquids. Art. 72.

7. Explain the Hydrostatic Paradox. Art. 74.

8. What is the principle of the Hydraulic Press? Art. 76.

9. Illustrate the power of the Hydraulic Press by an example. Art. 76.

10. Explain the difference between equilibrium of solids and liquids. Art. 77.

11. What are the conditions of equilibrium in the case of liquids of different densities. Art. 80.

12. Describe a Water Level and its use. Art. 82.

Art. 85.

13. Describe the principle of the spirit level. Art. 83.
14. Define a spring. Fountain. Artesian Wells.
15. Enunciate the principle of Archimides. Art. 86.
16. What is a Hydrostatic balance? Art. 87.

17. Explain the principles of Floating Bodies. Art. 89. 18. Give examples and illustrate the principles of Flotation. Art. 90.

19. Explain the action of the swimming bladder of Fishes. Art. 91.

20. What is the safest position in the water? Art. 92. 21. Define Specific Gravity. Art. 93.

22. How do you find the specific gravity of bodies? Art. 93. 23. What is Nicholson's Hydrometer? Art. 94.

24. How do you find the specific gravity of a liquid by the bal ance? Art. 95.

25. Which is the heaviest solid? Liquid? Art. 95.

26. Describe Beaume's Arcometer. Art. 96.

27. Describe the principle and object of the Alcoholometer. Art. 97.

28. Define the Lactometer and its use. Art. 98.

GENERAL PROPERTIES OF GASES AND VAPORS.

1. What is the difference between gases and vapors? Art. 99. 2. How many known gases are there? Which have not been liquified? Art. 99.

3. Describe the composition and uses of the Atmosphere. Art.

100.

4. How is the expansive force of air shown? Art. 101. 5. How can you show that air has weight? Art. 102. 6. What can you say of Atmospheric pressure? Art. 104. 7. How does pressure vary as we ascend? Art. 104.

8. Explain the principle of the Madgeburg Hemispheres, not the apparatus. Art. 106.

9. What is the pressure on the square inch? Art. 107.

10. Pascal's Experiment in detail, and his mode of reasoning. Art. 108.

11. Define a Barometer, and explain its principle. 12. Describe the Cistern Barometer in all its parts. mometer. Art. 110.

Art. 109.

The Ther

13. Describe the siphon Barometer. Art. 111. 14. What are the requisites of a good Barometer? Art. 112. 15. Where are the fluctuations of the barometer greatest? Least? Art. 113.

16. How is the height of a Barometer for a day or year determined? Art. 113.

17. What are the causes of Barometrical fluctuation? Art. 114.

18. When does the barometer rise? Fall? Art. 114.

19. Explain the use of the Barometer as a weather glass. Art. 114.

20. Describe the difference between the Index and Siphon barometer. Art. 115.

21. On what principle can you measure the heights of mountains by a barometer? Art. 116.

22. What is height of the atmosphere? Art. 117.

23. How are pressures transmitted through gases? Art. 118. 24. What is the amount of pressure on the human body? Art. 119.

25. How is that pressure sustained? Art. 119.

26. Describe Mariotte's Law. Its consequence.

Art. 120, 121.

His Tube.

27. How is the tube used to verify his law? Art. 121.

28. Explain the Manometer and the different kinds. Art. 122. 29. Describe the Open Manometer. Closed Manometer. Art. 123, 124.

30. What is the object of the Manometers? Art. 124.

AIR PUMP.

1. What is an Air Pump? When and by whom invented? Art. 125.

2. Give a complete description of the air pump. Art. 125. 3. Explain clearly the action of the air pump. Art. 125. 4. How may the degree of rarefaction be measured? Art. 126. 5. Mention some experiments with the air pump. Art. 127. 6. How and why are articles of food preserved in vacuo? Art. 128.

7. What applications are made of this principle? Art. 128. 8. Explain the difference between the air pump and Condenser. Art. 129.

9. How is the degree of condensation measured? Art. 129. 10. State the effect of condensed air on combustion. Life. Divers. Art. 129.

11. Describe an Artificial Fountain. Art. 130.

12. Describe Hero's Fountain.

131.

How prepared for use? Art.

13. Describe an Intermittent fountain. Art. 132.

14. Explain the principle of the Atmospheric Inkstand. Art. 133.

WATER PUMPS.

1. What is the difference between an air-pump and a water pump? Art. 125–134.

2. Describe in all its parts the Suction and Lifting pump. Art.

135.

3. Explain the action of this pump. Art. 135.

4. What and how many forms may be given to the force pump? Art. 136.

5. What is the difference between a Fire Engine and a pump? Art. 137.

6. How is the fire engine supplied with water? Art. 137.

7. How high may water be raised by the forcing pump? Art. 138.

8. Describe a Siphon, and tell when it may be used with advantage. Art. 139.

9. Explain the principle and action of the Siphon. Art. 139. 10. Describe the Siphon of constant flow. Art. 139.

BUOYANCY OF THE ATMOSPHERE.

1. Describo the principle of the Baroscope and its use. Art.

140.

2. Give the law of buoyancy, and tell when a body will rise in the air. Art. 140.

3. Describe a Balloon and its use. Art. 141.

4. What can you say of the history of ballooning? Art. 141. 5. With what are balloons filled? Tell how they are filled. Art. 142.

Art. 142.
Art. 142.
Art. 143.

6. How is the ascensional power regulated? 7. What is the use of the barometer? 8. Describe a Parachute and its use. 9. Mention some remarkable balloon ascensions. Art. 144. 10. Describe the uses of balloons. The great American voyage. Art. 144.

A USTICS.

1. Define Acoustics. Sound. What is its cause? Art. 145, 146.

2. How is sound transmitted? Art. 146.

What is a sonorous body?

Art. 148.
Art. 148.

3. What is a medium? Explain the vibrating cord. Art. 146. 4. How is sound imparted to the auditory nerve? 5. Explain how two sound waves produce silence. 6. What can you say of sound in vacuuo? Why? Art. 149. 7. What can you say of the propagation of sound in liquids and solids? Art. 150.

8. How is it shown that the earth transmits sound? Art. 151. 9. What is the velocity of sound? Art. 151.

10. Do all sounds travel with equal velocity? Art. 152.

11. Explain the reflection of sound. What is an echo? Art.

154.

12. Explain the causes of echoes. What is a Resonance? Art. 155.