Blog post by Russell Johnson Curator/Librarian History & Special Collections for the Sciences UCLA Library Special Collections

Card 55: The magic lantern. Optical cards by Mary Lewis, Camp Hill, December, 1828 (BIOMED Ms. Coll. no. 347 RARE)

A mini-exhibit for August 2014 asks (but does not answer) the question: Who was Mary Lewis of Camp Hill (Birmingham, England?) and, in 1828, why did she make 58 carefully handwritten, illustrated flash cards which addressed problems, phenomena, and experiments in optics and vision?

Card 2: A ray of light. Optical cards by Mary Lewis, Camp Hill, December, 1828 (BIOMED Ms. Coll. no. 347 RARE)

Mary Lewis’s cards (BIOMED Ms. Coll. no. 347 RARE), each with a standard embossed border, were purchased by the History & Special Collections for the Sciences section of UCLA Library Special Collections from Samuel Gedge, a dealer in antiquarian books, manuscripts, and ephemera. They are on display at the Louise M. Biomedical Library (1^st floor lobby/research commons) through Labor Day, 2014.

Card 33: The angle of vision. Optical cards by Mary Lewis, Camp Hill, December, 1828 (BIOMED Ms. Coll. no. 347 RARE)

This mini-exhibit is part of an occasional series, Well, Well, and What Have We Here, which brings to light (no pun intended) surprising, unexplained, and sometimes unexplainable items from or added to the collections. Explanations are welcomed.

Card 38: To find what proportion the size of the picture (card 36) bears to the size of the object. Optical cards by Mary Lewis, Camp Hill, December, 1828 (BIOMED Ms. Coll. no. 347 RARE)

The cards are titled:

1. [Title]
2. A ray of light
3. In the same medium, the rays of light are in straight lines
4. Rays of light may be bended
5. The same joining of mediums will bend some rays and not others
6. A ray passing obliquely through a plane glass goes on afterward parallel to its first direction though not in the same line
7. An angle
8. The angle of incidence
9. The angle of reflection
10. To see an object reflected from a plane looking glass
11. Parallel rays of light
12. Converging rays
13. Diverging rays
14. The eye sees an object by rays diverging from all the visible points of its surface
15. A pencil of rays, and a radiant point
16. A focus
17. A double convex lens or glass, seen edgewise
18. A plano-convex lens seen edgewise
19. A double concave lens seen edgewise
20. A plano-concave lens seen edgewise
21. A meniscus or concavo-convex lens seen edgewise
22. The radius of convexity of concavity of lenses
23. A triangular prism seen end-wise
24. The focus of the sun's parallel rays when transmitted through a double convex lens
25. Parallel rays become parallel again by passing through two convex lenses placed parallel to each other & at double their focal distance
26. The focus of the sun's (or any other) parallel rays, transmitted through a plano-convex lens
27. Rays diverging from a radiant point in the focus of a lens are parallel after passing through the lens
28. Rays diverging from a radiant point between a convex lens and its focus will continue to diverge, though in a less degree, after passing through the lens
29. Rays from a radiant point beyond the focal distance of a convex lens will, after passing through the lens, converge to a point or focus on the other side of the lens
30. Parallel rays passing through a double concave lens
31. Parallel rays passing through a plano-concave lens
32. Parallel rays passing thro' a solid sphere or globe of glass
33. The angle of vision
34. Why an object appears smaller and smaller as we recede further and further from it
35. A convex lens magnifies the angle of vision, and why
36. Rays from an object passing thro' a convex lens, will make a picture of the object in a dark room
37. To form the picture mentioned on card 36, the object must be farther from the lens than the focal distance of the lens
38. To find what proportion the size of the picture (card 36) bears to the size of the object
39. The camera obscura
40. The multiplying glass
41. An artificial eye
42. The human eye, with its coats and humours
43. The sclerotica & cornea of the eye
44. The choroides and ligamentum ciliare of the eye
45. The retina and optic nerve of the eye
46. The pupil and aqueous humour of the eye
47. The crystalline and vitreous humours of the eye
48. The manner of vision
49. Why an object appears large when it is near the eye, and small when far from the eye
50. Three patches being stuck on a board, to lose sight of the middle one, whilst both the others are visible
51. The use of convex spectacle
52. The use of concave spectacles
53. Single microscope
54. Refracting telescope
55. The magic lantern
56. The phantasmagoria lantern
57. The polyphantasma
58. Prismatic colours.

Card 48: the manner of vision. Optical cards by Mary Lewis, Camp Hill, December, 1828 (BIOMED Ms. Coll. no. 347 RARE)