Rev. Mr Eisdale*s Observatiom on Ground Ice, 167 



and inhabits for a certain period a palace placed on a higher 

 elevation. No educated person in Germany doubts the organic 

 function of he earth, to which also the cholera itself has been 

 ascribed ; and when a more general regard to nature advances 

 to the south, the sacred woods will again gradually surround 

 Rome, large vine branches entwine themselves round the elms, the 

 hills be thus again covered, and the malaria reduced within limits. 

 The fact is not without interest, that all real malaria districts 

 are of volcanic formation, and that they are often to be found at 

 the boundary of volcanic and non-volcanic rocks. That the 

 district of the Aderner sea was formerly exceedingly unhealthy 

 is certain ; and the same was the case with the Monte Gauro or 

 Ba?'baro, where at that period the best wine was produced, but 

 since the formation of the Monte Nuovo by a volcanic eruption 

 of 1538, between the sea and the hill, the spot has become 

 healthy ; but, at the same time, since that event it has been 

 found impossible to grow even tolerable ,wine in a place where 

 such nectar was formerly obtained. On the other hand, it is 

 known that it is only at a recent period that Monte Fiascone has 

 produced its nectar. Whoever may make the malaria the sub- 

 ject of his investigation will find a host of facts which he may 

 collect, and from them make out a history of this difficult and 

 little known subject. 



Observations on Ground-ice. By the Rev. Mr Eisdale. 

 (Communicated by the Author *.) 



On the 28th of December 1831, I read a paper at the meet- 

 ing of this Society, directing the attention of the members to a 

 particular kind of ice, which seems to be formed in direct oppo- 

 sition to the ordinary laws of congelation. The ice to which I 

 allude commences at the bottom of the water, and extends up- 

 wards to the surface, and it is produced only in the most rapid 

 and most rugged streams. This is exactly the reverse of the 

 usual process of congelation, which takes place in stagnant 

 water, commencing at the sides of the river or pond, and gra- 

 dually extending over the surface ; when it thickens downwards 

 towards the bottom, and if the frost is sufficiently intense, con- 



• Read before the Philosophical Society of Perth, on the 28th Dec. 1831. 



