674 OPTIC PROJECTION 



II. ARTIFICIAL CAMERA OBSCURA 



No one knows who first designedly arranged a darkened room with a white 

 wall or screen oh one side, and on the other a small opening facing some object 

 or scene that could be brightly illuminated. All we know is that the earliest 

 accounts of the pictures in a dark place are in connection with the explanation 

 of some other phenomenon, and not to show that such pictures were possible. 

 It was also recognized in the first statements, as in the works of Aristotle and 

 of Euclid, that as light rays extend in straight lines, that those from an object 

 must cross in passing through a small hole, and hence the images beyond the 

 hole in the dark place must be inverted, the top being below and the right being 

 left. 



According to Wiedemann and Werner, the Arabians, Iban Al Haitem (1039 

 A.D.), and Levi Ben Gersen (1321-1344), gave descriptions which clearly 

 belong to the camera obscura. However, that may be, we have the illustrated 

 manuscripts of Leonardo da Vinci, which not only describe the phenomena 

 of the camera obscura, but give pictures which are unmistakable. The pic- 

 tures and descriptions are in connection with his explanation of vision. As 

 Leonardo died in 1519, these manuscripts arc of an earlier date, probably before 

 1500 A.D. (See especially folio 8 of Ms. D.) 



Also in the accounts of eclipses, etc., of the astronomers Reinhold, Frisius 

 and Moestlin, they very clearly describe and give figures of the arrangement of 

 the dark room pictures (1540-1545) ; and in the quaint old volume of Cardanus 

 (De Subtilitate, 1550), there is a very graphic description of the means of 

 getting dark room pictures and of their appearance. Baptista Porta, in 1558, 

 in his Natural Magic, also gives a good description. Porta is credited in the 

 popular mind with the invention of the camera obscura, but as seen from the 

 above, it is a natural thing, and man had got camera pictures by design before 

 Porta was born. The Natural Magic of Porta was very popular in its day, 

 and was translated from the Latin into most modern languages, hence it is 

 intelligible that people thought him the inventor, as he gave credit to no one, 

 and gave out that many of the things had never been known before. To credit 

 him with the discovery of the marvelous things he describes would be like 

 making the modern magazine writer the inventor or discoverer of the wonder- 

 ful things he describes. In justice to Porta, it must be said that he states in 

 the preface to his book that he has consulted all libraries, and has visited many 

 skillful artisans to find out all the secrets. 



It may be stated in passing, that the name "Camera Obscura" was not used 

 by Porta, nor the others mentioned above. They used expressions like these: 

 cubiculum obscurum, cubiculum tenebricosum, conclave obscurum, locus 

 obscurus, etc. The first occurrence of the name "Camera Obscura" found by 

 us is in the Paralipomena of Kepler, (1604), p. 209 of the original, p. 261 in 

 the Opera Omnia, vol. ii. Kepler also uses the expression, "camera clausa," 

 vol. ii, p. 160. 



