44 



M (; — ('"') in which M is constant, t the temperature of the air, 

 and t'" the temperature of the condensing surface. 



The principal object of the experiments was to determine mean 

 values of the co-efficients m and M. The data and results necessary 

 for this purpose were contained in the two tables before alluded to, 

 and the following small table merely exhibits the mean values. 



Mean Values. Velocity of Current per 1". Number of Experiments. 



M = 0-12 Insensible 15 



= 18-3 4-12 feet 11 



8-24 8 



14-8 8 



20-6 11 



It is to be remarked, that the value of M, as given above, is only 

 applicable when the air in contact with the cold surface is free to 

 descend by its own weight, and that when, from any impediment to 

 its escape, the air is not changed, there is scarcely any sensible con- 

 densation of vapour on thd* cold surface. 



The paper concluded by examininnr, in connection with the pre- 

 ceding results, the theory proposed by Professor Phillips in explana- 

 tion of the increment received by rain in the course of its descent to 

 the earth. This theory, as is well known, ascribes the increment to 

 to the continual condensation of vapour on the cold surfaces of the 

 drops ; and the author of this paper attempted to prove, that when 

 the data assumed were the most favourable to the theory which the 

 case admitted of, the observed increment of the rain was 635 times 

 greater than would be accounted for by the rate of the experiments. 



3. On the Poison of the Cobra da Capello. By Dr J. Ruther- 

 ford Russell. Communicated by Dr Gregory. 



The poison is of an amber colour, has a faint animal odour and an 

 acrid taste. When treated with alcohol or ether it separates into two 

 portions — the one soluble and the other insoluble. From some experi- 

 ments Dr Russell made he concluded that both were poisonous, but is 

 inclined to believe the soluble to be the more poisonous of the two. 



He gave a detailed account of a series of experiments made upon 

 some rabbits and a dog. The effect of the insertion of a small 

 portion of the poison into a wound in a rabbit was in almost every 

 case to produce death, generally preceded by stupor and sometimes 

 by convulsions. The lungs were found gorged with blood in several 



