1820.] Rot/al Geological Socieh/ of Cornwall. 143 



into all rlo-orous forraulai of double vefraction ; and another 

 strikino- instance is presented of the inherent distinction between 

 the difterent coloured molecules of light. At the same time, 

 continued the author, by the complete explanation this principle 

 affords of all the more perplexing anomalies in the tints, the 

 theory of oscillation stands relieved of every difficulty, and may 

 be received as adequate to the representation of all the pheno- 

 mena of the polarized rays, and entitled to rank vAih the fits of 

 easy transmission and reflection as a general and simple physical 



law. 



At this meeting a paper, by Dr. Granville, was read, entitled 

 *' An Account of a Case of Ovario-gestation." The subject of 

 this c^ise having died suddenly, and under circumstances rather 

 peculiar, an examination of the body was instituted to discover 

 the cause of her decease. On opemng the abdomen a quantity 

 of blood was found, and a tumour about four times the size of a 

 hen's egg obstructed the view of the internal parts of generation. 

 This tumour rested on the left portion of the uterus, and upon 

 examination was found to be connected with the left ovarium. 

 At the inferior part of this tumour diaphanous membranes, includ- 

 ino- the rudiments of a fcetus of about four months' growth, were 

 observed. Upon further examination, it was found that the 

 ovarium where it enveloped the placenta had been ruptured by 

 the growth of the fcetus, and to the loss of blood thus occasioned 

 the death of the mother was attributed. The uterus v/as consi- 

 derably developed ; the right ovarium was healthy ; the left 

 fallopian tube was also sound, and unattached to the tumour. 

 The different stages of the dissection were illustrated by beauti- 

 ful drawings made by Mr. Bauer. 



Jai(. 20. — A paper, by Edmund Davy, Esq. was begun, enti- 

 titled " On some new Combinations of Platinum." 



KOYAL GEOLOGICAL SOCIETY OF CORNWALL. 



Sixth Annual Report of the Council. — The state of compara- 

 tive maturity to which the Society has now arrived affords less 

 interesting matter for remark than during its early progress. 

 The Council, therefore, in discharging this their annual duty to 

 the members, have little left them to do but to call their atten- 

 tion to the respectable rank which the Institution has attained, 

 and to urge the necessity of their continued patronage to insme 

 its stability. 



Independently of the intrinsic advantages of an Institution of 

 this kind in gradually adding, by the labours of its members, to 

 the knowledge of the physical structure of Cornwall, it possesses 

 a secondary value by attracting to this part of the county indi- 

 viduals eminent for their genius and scientific acquirements, 

 •whose presence cannot fail to be useful to any place which they 

 visit. 



Owing to expenses incidental to the completion of a new 



