320 



and Stat. Soc, March 22, 30 pp. 8vo., with Map, New York? 

 UQO.—From W. P. Fonlke. 



Paulding (J. K.) — Prof. Trego announced the death of a 

 member of the Society, the Honorable James K. Paulding, 

 April 4th, 1860, aged 81. 



Dr. Emerson called the attention of the Society to a fact 

 in optics, which seems to have been but little noticed. A very 

 simple experiment illustrating the combined action of the 

 mental and optical faculties concerned in vision. A person 

 standing before a mirror, holding a picture before him, with 

 its face also towards the mirror, will find the reflection of the 

 hands or right and left sides of a picture reversed, the right 

 hand appearing the left and the left the right. But this 

 reversion does not extend to the person holding the picture, 

 or others by his side, whose right and left sides are recognized 

 only as right and left. This illustrates the effects of education 

 of the eye, which having recognized through repeated obser- 

 vations the true relations of the two sides and hands, admits 

 without hesitation the mental evidence, but refuses to accept 

 any but optical evidence from the flat surface of the picture. 



Dr. Leyburn, pursuant to appointment, read the following 

 obituary notice of the Rev. J. Addison Alexander, a deceased 

 member of the Society. 



OBITUARY NOTICE OF JOSEPH ADDISON 

 ALEXANDER, D.D. 



BY JOHN LEYBURN, D.D. 



Joseph Addison Alexander, was the third son of the late 

 Archibald Alexander, D.D., of Princeton, N. J., and was 

 born in the city of Philadelphia, April 24th, 1809. On his 

 maternal side he was the grandson of James Waddell, the 

 celebrated blind preacher of Virginia, immortalized by Wirt 

 in the British Spy, His father having removed from Phila- 

 delphia to Princeton, young Alexander became a student of 

 the College of New Jersey, where he graduated in 1826, with 

 valedictorian honors, a great achievement for a youth of seven- 



