238 Mr. M. Carey Lea on 



(whatever that may mean) into one huge dark inert mass of 

 uniform temperature in which no life is possible, this much, 

 at least, is included in what we do know — viz., that we shall 

 not have then got rid of the static energy of gravitation ; 

 and I strongly suspect that if we journeyed out to Antares 

 or to Aldebaran, we should meet with intelligent beings 

 who would express the utmost astonishment that we could 

 ever have framed a principle leading to such a universal 

 catastrophe. 



XXVI. On Gold-coloured Allotropic Silver. — Part I. 

 By M. Caeey Lea *. 



[Plates I.-II1.] 



THE object of the present paper (which may be considered 

 as a continuation of that published in the American 

 Journal of Science for June 1889) will be: — 



1st. To describe the reactions of gold-coloured allotropic 

 silver. 



2nd. To show that there exists a well-characterized form of 

 silver intermediate between the allotropic silver previously 

 described and ordinary silver, differing in a marked way from 

 both. 



3rd. To prove that all the forms of energy act upon 

 allotropic silver, converting it either into ordinary silver 

 or into the intermediate form. Mechanical force (shearing- 

 stress) and high-tension electricity convert it directly into 

 ordinary silver. Heat and chemical action convert it first 

 into the intermediate form, then into ordinary silver. The 

 action of light is to produce the intermediate form only, and 

 even the most prolonged action at ordinary temperatures does 

 not carry it beyond this. 



4th. To show that there exists a remarkable parallelism 

 between the action of these forms of force on allotropic silver 

 and their action on the silver haloids, indicating that it is 

 not improbable that in these haloids silver may exist in the 

 allotropic condition. 



Beactions. 



The most characteristic reactions of gold-coloured allotropic 

 silver are those with the strong acids. When normal silver re- 

 duced with milk sugar and alkaline hydroxide is left in contact 

 with strong hydrochloric acid even for several hours, there is no 



* From an advance proof communicated by the Author, to whom we 

 are also indebted for the beautiful Plates illustrative of the paper. — W. F. 



