S34> Cambridge Philosophical Society. 



I have here stated may induce others to join in carrying so desirable 

 an object into execution. 



Mr. Baily stated to the meeting that further accounts had been 

 received from America, relative to the annular eclipse of the sun on 

 the 18th of September last. Professors Henry and Alexander ob- 

 served it at Princetown College, New Jersey. About eighteen seconds 

 before the formation of the ring, the moon's limb became brightly 

 illuminated. An appearance similar to a row of beads was regarded 

 as the formation of the ring : the drops continued for a second or 

 two. Professor Alexander remarks, that the luminous arch round 

 the moon's dark limb, and the brush of light, were only partially 

 visible in his 4-feet Fraunhofer, with a yellow screen-glass, having a 

 slight tinge of green : but he saw them distinctly in his 3^-feet 

 DoUond with a red screen-glass, for about four minutes after the 

 rupture of the ring : whence it is inferred that the appearance of the 

 beads of light and the dark lines frequently noticed, may be com- 

 pletely modified by the colour, and consequently the absorbing power 

 of the screen-glass through which they are observed. 



It was noticed by most of the observers, that before the formation 

 and after the rupture of the ring, the edge of the moon off the sun 

 was distinctly visible, and illuminated for some distance within the 

 moon's surface. 



CAMBRIDGE PHILOSOPHICAL SOCIETY. 



April 29, 1839. — A meeting of this Society was held on Monday 

 evening. Professor Gumming, one of the Vice-Presidents, being in 

 the chair. Mr. Gregory exhibited various photogenic drawings, and 

 described the process by which they were prepared. Professor 

 Sedgwick gave an account, illustrated by various drawings, of the 

 geological structure of Cornwall, according to the new views re- 

 specting the place of its rocks in the order of the British strata to 

 which he and Mr. Murchison have recently been led. 



May 6. — A meeting of this Society was held on Monday evening, 

 Dr. Graham, the President, being in the chair. Professor Miller 

 made a communication on the Theory of Halos, with particular .re- 

 ference to Fi-aunhofer's views on that subject. Mr. Green read a 

 note, additional to a former memoir, on the Reflection and Refrac- 

 tion of Light. Mr. Gregory read a paper on Chemical Classifica- 

 tion. 



May 20. — A meeting of this Society was held on Monday even- 

 ing. Dr. Clark in the chair. Mr. Ansted made a communication on 

 the Tertiary Formations of Switzerland. Mr. Green read a memoir 

 on the motion of light through crystallized media. Mr. Whewell 

 read a note respecting the working of his Anemometer since his 

 memoir on that subject read May 1, 1837. The Anemometer had 

 since that time been in action at the Society's house, and at the 

 Cambridge Observatory ; but in consequence of the instruments be- 

 ng frequently repaired and improved, the observations were fre- 



