no 



The reading of the following paper was commenced : — 



1. Observations and Experiments on the coloured and co- 

 lourable matters in the Leaves and Flowers of Plants, 

 particularly in reference to the Principles upon which 

 Acids and Alkalies act in producing Red and Yellow or 

 Green colours. By Dr Hope. 



Professor Forbes shewed a specimen illustrative of the star-like 

 fractures of horizontal strata, as assumed in the theory of Eleva- 

 tion Craters. It was a stratum of crystallized chloride of calcium, 

 which had been accidentally fractured and elevated in Dr Christi- 

 son's laboratory by the sudden disengagement of steam beneath 

 during crystallization. 



Mr Robert Allan mentioned some remax-kable facts respecting 

 the disengagement of light during crystallization, communicated to 

 him by Professor Rose of Berlin. 



