CONTENTS. vii 



PACK 



CHAP. IV. 108. Anecdotes of the ourang-outang. 109. Analogy of 

 the skeleton of the ourang-outang to that of man. 110. Of the 

 brain to the human brain. 111. Intelligence of the wolf. 112. 

 Anecdote of the hawk, the cat, the eagle. 113. Of the dog. 

 114. Of the bear. 115. Intelligence of animals decreases with 

 age. 116. Man distinguished from other animals by the degree 

 of intelligence. 117. Lower animals are not endowed with re- 

 flection. 118. Inferior animals have methods of intercommu- 

 nication as a substitute for language. 119. Examples in the 

 cases of marmots, flamingoes, and swallows. 120. Intercom- 

 munication of ants. 121. Example in their mutual wars. 122. 

 Acts which cannot be explained either by instinct or intelligence. 

 123. Carrier-pigeons. 124. Domesticity and tameness . . 161 



THE SOLAR MICROSCOPE. 



Its utility. 2. The principle of its performance. 3. Why the 

 magic lantern does not serve the same purposes. 4. The illumi- 

 nating apparatus. 5. How to protect the object from heat. 

 6. The amplifying apparatus. 7. The adjustments. 8. The 

 screen. 9. The reflector. 10. Method of mounting the instru- 

 ment. 11. Arrangements for the room of exhibition. 12. 

 Preliminary adjustments. 13. The oxy -hydrogen and electric 

 microscopes 177 



THE CAMERA LUCIDA. 



1. Origin of the name. 2. Its use. 3. Method of applying it. 

 4. Explanation of its principle. 5. Precautions in using it. 

 6. Methods of correcting the inversion of the object. 7. 

 Amici's camera. 8. Magnitude of the picture. 9. Application 

 of camera to the microscope . . . . . . .185 



THE MAGIC LANTERN. 



Optical principle of the instrument. 2. Its most common form. 

 3. Magnifying power. 4. Precautions to be taken in the use 

 of the instrument. 5. Pictures on the sliders. 6. Opaque screen. 

 7. Transparent screen. 8. Phantasmagoria method of pro- 

 ducing it. 9. Exhibition with two lanterns. 10. Curious opti- 

 cal effects. 11. Dissolving views. 12. Application of the lantern 

 to the purposes of instruction in history and chronology. 13. 

 In geology. 14. In astronomy. 15. Use of solar system. 16. 

 Great utility of the lantern for this purpose. 17. Views of the 

 stars. 18. Nebulae and clusters. 19. Practical example of the 

 utility of this instruction. 20. Oxyhydrogen lantern. 21. Ap- 

 plication of electric light to the lantern 193 



