0? NATURAL HISTORY. 189 



which v/e are every way furrounded. On the other hand, 

 when near objects emit a feeble Ught only, compared with 

 that which proceeds from a remote objeft, as, for example, 

 when we view luminous bodies in the night, then very dif- 

 tant objefts make diftiiicl: pictures on the retina, and become 

 perfectly vifible. Hence a man, by placing himfelf in a 

 dark iituation, and looking through a long tube, without the 

 intervention of a glafs, may make a kind of telefcope, which 

 will have a confiderable effect even during the day. For 

 the fame reafon, a man at the bottom of a deep pit can fee 

 the ftars at noon. 



The lirft and greateft error in vifion, in the opinion of 

 many authors, arifes from the inverted reprefentation of ob- 

 je(fts upon the retina ; and they maintain, that, till children 

 learn the real polition of bodies by the fenfe of feeling, they 

 fee every objedl inverted. But new born animals, whether 

 of the human or brute fpecies, fee obje<Sls, not inverted, but 

 in their real politions, independently of all experience, or of 

 any opportunity of re(5lifying the fuppofed illufion by the 

 {en{e of touch. Animals fee objects in their real pofition by 

 a lav; of Nature, and by the inftrumentality of the eye and 

 optic nerve. Were it not a law of Nature, or of the confti- 

 tution of animals, to fee obje£ls erefl, though their images be 

 inverted on the retinae, an inverted objedl could not poffi- 

 bly appear inverted ; for, in this cafe, we fhould not be 

 obliged to have recourfe to experience, or to the fenfe of 

 feeling. Belides, it is an eftabliflied fa<5V, that blind men, 

 who had been reftored to fight by chirurgical operations, in- 

 ftantly faw objedls in their real pofition*. There is no rela- 

 tion to the principles of optics, in the fenfation of feeling, by 

 which an image, painted by rays of light on foft white ner- 

 vous terminations, is conveyed through a mofl opaque body, 

 in a long courfe of perfefl darknefs, to the brain. Indeed, 



• Haller. Phyfiol, torn. ». page 87. 



