404 Sikx in the Bath Waters. 



I found that it acquired a vitreous appearance after having fuffered a very confiderable 

 eflervtfcence fimilar to that in making glafs. I have already mentioned that this fub- 

 ftance refifted the aflion of the nlarine, nitric and vitrioHc acids. 



From the foregoing experiments, I am led to believe, that this infoluble fubftance is 

 filicious earth; I have, however, been very cautious and exaft in my experiments to 

 afcertain it, becaufe no one who has hitherto analyfed thefe waters, has mentioned any 

 thing concerning its prefence in them. It is a faft generally admitted, that water is 

 capable of holding in folution a very fmall portion of filicious earth, but under fome 

 eircumftances, a confiderable quantity as in the Geyfer and Rykum \vaters, fo admirably 

 proved by Hx. Black. The uniform temperature of the Bath waters would lead us to 

 conclude, that 'they acquire their heat from a continued and powerful operation in the 

 bowels of the earth. The length of time that they have been known to pour forth their 

 hot ftreams, would induce us to think that the caufe is uniform, and very deeply fituated 

 in the bowels of the earth. I beg leave to offer a conjefture refpefting that regularity 

 «f their temperature ; which is, that at fome great depth in the earth they are at a very 

 high temperature, and that in coming up to the furface of the earth, their temperature 

 is lowered to the degree they are found to polTefs. Thus they appear to me to be an 

 analogous to the Geyfer in Iceland, and that at a certain depth they would be found to 

 have the fame appearances. That they are liot of the nature of common fprings of water 

 is evident to me from their not being affefled by the viciflitudes of weather, or by the 

 alternation of wet and dry feafons. As I do not find that there is any portion of dif- 

 engaged alkali in thefe w-*^rs, and as I cannot difcover any fubftance which can render 

 filicious earth foluble '7'"ihem, I muft hazard the following conjefture refpefting its 

 ftate of combination. i.uppofe that at a confiderable depth thefe waters are of a tem- 

 perature capable of difrolving many fubftances, which water is incapable of, at any 

 ordinary degree of heat, and among them filicious earth. This earth would be there- 

 fore extremely divided, and fufEciently fo I apprehend, for a part to remain fufpended,. 

 or even diffolved by them, when they arrive at the furface of the earth. On evapora- 

 tion, I fuppofe, thefe minute particles to coalefce fufficiently to prevent any frefh 

 union with water. There is a faft which corroborates my opinion, which is that after a 

 few years, fo great is thedepofition of a fine fand in the refervoir, that they are obliged 

 to clear it away to prevent the pumps, &c. from being obftrufted> 



(To be concluded in our ncKi.J 



Aieouni 



