'^i,^ 



IMMK'ivEDlXdS ^^ 



ov iHi; 



EOYAL SOCIKTY 



^o:r 19: 4. 



VOL. XX \ I. 



Edited by - - 



A. B. \X'ALKOM, B.Sc 



Till' Aiitliors III p,iper.< ure alone respuiixilde for the statenieiit^ iinuh 

 iiiuJ tfie opinions e-rjirfssed therein. 



l-;-.INTI-D I'Ol: 'J'HE SCH'IETY 



i;y 

 H. POLE \- CO. PfilNTKItS. F.LIZAP.F.TH S'l'ItEF.-;'. BlIISBAXK 



