235 



verification can scarcely be imagined than that from flic admeasure- 



nient of Turbo duplicates. 











Geom. 



ratio, 



1.18. 





Calculated. 









Measured 



1.31 - 



- 



- 





1.31 



1.1098 



- 



- 





1.12 



.9401 



- 



- 





.94 



.7965 



- 



• 





.8 



.6747 



- 



- 





.67 



.5716 



- 



- 





.57 



.4842 



- 



- 





.48 



.4102 



- 



. 





.41 



Mr. Lea also exhibited to the Society a beautiful and nearly per- 

 fect specimen of an Ammonite, from the Oxford Clay, Chippenham, 

 England, recently described in the Magazine of Natural History, 

 and which presented, entire, the process extending from the aperture, 

 which he passed some remarks upon. 



Mr. Justice stated, that he had examined the appearance of 

 the moon, to verify the observations made at New Bedford, 

 and that the phenomena visible were perfectly explicable, with- 

 out supposing that any combustion was going on at the surface 

 of the satellite. 



Professor Bache stated that his attention had recently been 

 particularly called, by a letter from M. Quetelet, Secretary of 

 the Academy of Sciences of Brussels, to the general instruc- 

 tions for simultaneous observations of natural phenomena, issued 

 by the Academy. Co-operation in the system of observations 

 by observers in the United States being very desirable, Prof. 

 Bache asked leave to offer the following resolution : 



" Resolved, That a Committee of five members be appointed, to 

 report to the Society what measures may be taken, most effectually 

 to secure co-operation, by observers in the United States, in the sys- 

 tem of observations of periodical natural phenomena, forming the sub- 

 ject of the instructions of the Brussels Academy of Sciences." 



This resolution was adopted, and the following Committee 

 appointed: — Prof. Bache, Dr. Patterson, Mr. Frazer, Dr. Gris- 

 com and Mr. Lea. 



Prof. Bache communicated observations which had been 



