March 21st, ipii.] PROCEEDINGS. xxiii 



In a previous paper the author stated he had found 

 that the percentage of Carbonic Acid gas contained in the 

 exhaled air from the lungs was greater when breathing dry 

 than when breathing damp air, also when breathing in 

 Mountainous districts where the atmospheric pressure was low 

 than when breathing in the Valley, and, again, was greater when 

 breathing in the Valley than when breathing at the bottom of a 

 deep Coal pit where the pressure is still greater. The experi- 

 ments recorded in the present paper were made upon the 

 exhaled air from three men and one boy, and upon guinea 

 pigs and mice, and the results from all shew that, as a rule, when 

 the barometer fell, the percentage of Carbonic Acid in the 

 exhaled air rose, and, when the barometer rose, the percentage of 

 Carbonic Acid fell. As the air became more moist the per- 

 centage of Carbonic Acid fell, and it rose when the air became 

 drier. 



There was a lower percentage of Carbonic Acid in the 

 exhaled air when the weather was warm than when it was cold. 



The paper will be published in full in the next volume. 



Miss Margaret C. March, B.Sc, read a paper, communi- 

 cated by Dr. Hickling, entitled : " Studies in the Morpho- 

 genesis of certain Pelecypoda. III. The Ornament of 

 In'goma davellata and some of its Derivatives." 



The paper is printed in full in the Alemoirs. 



General Meeting, April 4th, 191 1. 



Mr. Francis Jones, M.Sc, F.R.S.E., President, 

 in the Chair. 



Mr. Arthur Adamson, A.R.C.S., Lecturer in Physics in 

 the Municipal School of Technology, Manchester, and Mr. 

 C. G. Darwin, B.A., Reader in Mathematical Physics in the 

 University of Manchester, were elected ordinary members of 

 the Society. 



