OF ARTS AND SCIENCES. S3 



which makes it extremely probable that M. Meyer has hit upon 

 the correct one. If, when the eyelids are adjusted so as to 

 develop the two vertical beams in great length and bright- 

 ness, we cautiously lift away the loioer eyelid from the cor- 

 nea without changing the distance between the two eyelids, 

 we observe that the upper beam instantly disappears ; and so, 

 on lifting the upper eyelid, the lower beam vanishes. This 

 is just what ought to happen according to Meyer's view of 

 the origin of the beams. The lifting of the eyelid, by break- 

 ing up the convexity of liquid, must of course put a stop to 

 the fan-shaped refraction, and therefore extinguish the vertical 

 beam corresponding to it above or below the luminous object. 

 As the reflection from the surface of the eyelid would be but 

 little altered by the slight removal from the cornea, we ought 

 on the hypothesis of reflection .either to find the two vertical 

 beams unaltered, or that beam which is on the same side as 

 the eyelid merely a little feebler and shorter. If, again, we 

 revolve one of the eyelids entirely out of the range of action, 

 while the other is retained in its, place, the beam which dis- 

 appears is found to be for the lower lid the upper beam, and 

 for the upper lid the lower beam, as ought to be the case ac- 

 cording to Meyer's explanation. 



Professor Peirce made a communication on the relations of 



curves of which the equations are < q n I ' ^^ which the 



functions are derived from the equations/(a;-{-2/ • V--l)== 

 P -f Q V^=l. 



Professor Agassiz added some remarks, in which he pointed 

 out some interesting analogies, suggested by Professor Peirce's 

 communication, in certain organic forms in the vegetable and 

 animal kingdoms. 



Professor Cooke called the attention of the Academy to 

 some remarkable relations he had discovered between the 

 atomic weights of the elements ; and to some new facts which 

 a knowledge of those relations had led him to observe. He 

 considered the common classification of the elements as not 



