150 ANNUAL OF SCIENTIFIC DISCOVERY. 



the size of the eye, and pierce with a fine needle a hole in the middle, 

 you will, on looking through that hole at a clear sky or a lighted lamp, 

 see a multitude of molecules floating about ; which molecules consti- 

 tute the air. We shall see whether the theory will obtain the sanction 

 of the Academy of Sciences, to which it has been submitted." 



An ingenious writer in the New Orleans Delta, who has given this 

 subject much attention, has published the following, communication. 

 The atomic globules which were rendered visible to M. Andraud, by 

 means of the perforated card, are not (fried molecules. I have been, 

 for some months past, familiar with this interesting experiment. The 

 beautiful globules seen by means of the hole in the card are the atomic 

 colorless globes which constitute the crystalline fluid within the eye. 

 M. Andraud supposes they are external and in the air, when the truth 

 is they are internal and within the chamber of the eye. 



The experiment may be tried, and the fact verified by any person, 

 in the following manner : Take a thick visiting-card and black it with 

 ink, or a piece of pasteboard opaque enough to forbid the transmission 

 of light through it, and perforate the center with a pin-hole. Place 

 the card between the eye and a candle-flame, or a globe-lamp, and not 

 more than two inches from the eve, and the same distance from the 



ti 



light ; but this distance will vary according to the convexity or flatness 

 of the seer's eye, who must adjust it till he finds his focus. Instead of 

 seeing the flame of the candle, the beholder now discerns a circular 

 disc the size of the iris of the eye. This disc is bright and planet-like, 

 and is crossed by innumerable lines like the fibres visible on the sur- 

 face of a magnified rose-leaf. It appears to be beyond the eye, between 

 the card and the light; and it is this illusion which deceived M. 

 Andraud, and led him to suppose that he saw a portion of the atmos- 

 phere magnified. But this visible disc is, in fact, a spherical section 

 of the fluidal crystalline lens within the chamber of the eye, strongly 

 illumined by the concentrated pencil of light, passing from the candle 

 into it through the minute hole in the card ; and the veined appear- 

 ance of its surface is the reticulated materia of the ordinarily transpa- 

 rent coat of the cornea rendered visible. The chamber of the eye 

 thus lighted up by the intense line of light passing into it through the 

 minute orifice, (Avhich acts as a strongly magnifying lens,) there is 

 conveyed to the optic nerve an image (exactly the size of the pupil 

 through which the ray passes) of a circular section of the crystalline 

 fluid, with its atomic particles intensely magnified. The spectacle is 

 one of surpassing wonder and beauty. Myriads of illuminated mole- 

 cules distinctly appear in tremulous motion in the bright fluid ; some 

 of them are simple globes, others are encircled by two or more con- 

 centric rings like exquisite miniatures of the planet Saturn, as seen 

 through a telescope. Some of them are transparent, like infinitely 

 small soap bubbles, and float about as lightly, while others are of the 

 white color of pearls. 



By contracting the eye, or by gently moving the head from side to 

 side, these beautiful millions of globular atoms are made to undulate 

 within the chamber of the eye, and change places, some ascending and 



