40 DR BREWSTER on the Existence of Two Netv Fluids 



ing theorists have limited their idolatry to two of the elements ; 

 but the existence of two new substances in minerals, one of 

 which combines a great degree of fluidity with the high expan- 

 sive power of the gases, renders it probable, either that these 

 substances existed at the formation of the globe, or that they are 

 the result of laws of crystallographic combination which have 

 escaped the notice of the philosophical geologist. Were such 

 fluids the product of the ordinary processes of crystallization, 

 they would occur in artificial as well as in natural crystals : 

 and, consequently, while they remain undiscovered in the cavities 

 of the first of these classes of bodies, we are entitled to attach a 

 new difficulty to the aqueous hypothesis. 



Had the two new fluids occurred only in one mineral, or in 

 minerals of a particular composition, they might have been sup- 

 posed to have some relation to the elementary principles of the 

 body, and to have arisen either from some accidental irregulari- 

 ty, which prevented them from crystallizing, or from the decom- 

 position of the matter subsequently to its crystallization. The 

 perfect identity, however, of the two fluids, as found in pure 

 Quartz, in Amethyst, in Topaz, and in Cymophane, minerals 

 brought from the most opposite parts of the globe, from Scot- 

 land, Siberia, New Holland, Canada, and Brasil, establishes the 

 universality of their existence, and adds to the probability of the 

 supposition, that they have performed some important function 

 in the organization of the mineral world. 



While the preceding facts thus obviously connect themselves 

 with our geological theories, they promise also to be of some use 

 in the practical branches of Physics. A fluid possessing such a 

 high expansive power would be invaluable in the construction of 

 delicate Thermometers, and various other philosophical instru- 

 ments ; while its extreme fluidity would enable us to construct 

 levels of singular delicacy. If the resources of the chemist shall 



