When and by whom its true figure was discovered.
ON THE SUPPOSED DIVISION OF THE EXTERIOR RING OF SATURN.
Kater’s, Short’s, Quetelet’s and Decuppis’s observations
1. DESCRIPTION OF THE EARL OF ROSSE’S LARGEST TELESCOPE.
Composition of the speculum, and the process of casting it--Mode of grinding and polishing it--Manner in which it is filled up--Expenses incurred in its construction--Results of observations which have been made with it--Two views representing this instrument and the buildings connected with it--Sir J. South’s remarks and anticipations
2. HINTS TO AMATEURS IN ASTRONOMY RESPECTING THE CONSTRUCTION OF TELESCOPES.
1. Representation of the diminution of the intensity of light. 22
2. Illustrative of the refraction of light. 43
3. Representing the angles of incidence and refraction. 44
6, 7, 8. Parallel, converging, and diverging rays. 66
9, 10, 11. Passage of parallel, diverging, and converging rays through convex lenses. 67
12. Passage of parallel rays through concave lenses. 69
14. Angle of incidence and reflection. 83
15. Images as reflected from a plane mirror. 84
16. Illustrative of reflections from a plane mirror. 85
17. Shewing how the image in a plane mirror is twice the length of the object. 86
18. Reflection from _concave_ mirrors. 87
20. Parallel rays as reflected from concave mirrors. 91
21. Diverging rays as reflected from concave mirrors. 91
22. Images formed before concave mirrors. 93
23. Images formed behind concave mirrors. 96
24. Illustrating the magnifying power of concave mirrors. 97
25. Inverted images formed in the front of concave mirrors. 98
26. Illustrative of deceptions produced by concave mirrors. 100
27, 28. Experiment with a bottle half filled with water. 101
29. Effect of extraordinary refraction on ships at sea. 109
30. Experiment for illustrating the causes of uncommon refraction. 117
32. Different foci of coloured rays in convex lenses. 129
33. Experiment to show the different foci of red and violet rays. 129
34. Illustrative of the prismatic colours. 136
35. Explanatory of refraction and reflection from drops of rain. 147
37. Images of objects formed in a dark chamber. 187
39, 40. The portable Camera Obscura. 195, 196
40, 41, 42. Illustrative of the angle of vision, and the apparent magnitude of objects. 206, 207, 208