84 



6. The characteristic law of polarization in the case of light holds 



in that of heat; viz., that the intensities in rectangular po- 

 sitions of the polarizing and analyzing plates are comple- 

 mentary to each other. 



7. As a necessary consequence of the above, confirmed by expe- 



riment, heat is susceptible of circular and elliptic polariza- 

 tion. 



8. The undulations of obscure heat are probably longer than those 



of light. A method is pointed out of deducing their length 

 numerically. 



2. Supplementary Notice on the Chemical Analysis of the 

 Animal Remains of Burdiehouse. By Arthur Connell, 

 Esq. 



Since the author's former communication to the Society, he has 

 analyzed a portion of a bony fin-ray from the limestone belonging to 

 a fossil fish which has been designated by M. Agassiz, Gyracanthus 

 formosus. 



The constituents were found to be — 



Phosphate of Lime, with a little Fluoride of Calcium, 



Carbonate of Lime, 



Siliceous matter, .... 



Potash and Soda, partly as Chlorides, 



Bituminous matter, 



Phosphate of JIagnesia, .... trace 



Animal matter, trace 



99-20 



He has also analyzed a portion of the fossil scales embedded in the 



limestone. These scales belong to a fossil genus of fish, to which the 



name of Megalichthys has been given by M. Agassiz, and which is 



supposed to approach in character to the Lepisosteus, or Lepidosteus 



of Agassiz. The scales were about three-fourths of an inch long by 



somewhat less in breadth, and possessed a fine lustre, and the usual 



delicately punctured surface. They were found to contain — 



Phosphate of Lime, with a little Fluoride of Calcium, 50-94 



Carbonate of Lime, ....... 11-91 



Siliceous matter, ....... 33-10 | qq.qq 



Water, 3-48 J 



Potash and Soda, "4:7 



Bituminous matter, ....... '12 



Phosphate of Magnesia, .... trace 



Animal matter, . .... trace 



100-02 



