On the Experimental Relations [1857. 



the gold solution gradually produces the ruby fluid at the 

 bottom, but the action is very slow. If the phosphorus be 

 attached to the side of the bottle, but always beneath the 

 surface of the solution, the streams of ruby fluid may be seen 

 moving both upwards and downwards against the side of the 

 glass, and forming films in the vicinity of the phosphorus 

 perfect in their golden reflexion, and yet transmitting light of 

 ruby, violet, and other tints, thus giving, first a proof that the 

 particles are gold, and then connecting the present condition 

 of the gold with that of the films already described. On the 

 other hand, the phosphorus may be excluded and the sulphide 

 of carbon employed alone ; for when it and the solution of gold 

 are shaken together, the gold is reduced and the ruby fluid 

 formed ; but it soon changes to purple or violet. 



A quick and ready mode of producing the ruby fluid, is to 

 put a quart of the weak solution of gold (containing about 0*6 

 of a grain of metal) into a clean bottle, to add a little solution 

 of phosphorus in ether, and then to shake it well for a few 

 moments : a beautiful ruby or amethystine fluid is immediately 

 produced, which will increase in depth of tint by a little time. 

 Generally, however, the preparations made with phosphorus 

 dissolved in sulphide of carbon, are more ruby than those 

 where ether is the phosphorus solvent. The process of 

 reduction appears to consist in a transfer of the chlorine from 

 the gold to the phosphorus, and the formation of phosphoric 

 or phosphorous acids and hydrochloric acid, by the further 

 action of the water. 



The fluids produced may easily be tested for any gold yet 

 remaining unreduced, by trial of a portion with solution of 

 protochloride of tin. If any be found, it is easily reduced by 

 the addition of a little more of the phosphorus in solution. 

 After all the gold is separated as solid particles, the fluid may 

 be considered in its perfected state. Occasionally it may 

 smell of phosphorus in excess, even after it has been poured 

 off from the deposited particles of it and the sulphide. In 

 that case it is easy to deprive it of this excess by agitation in 

 a bottle with air. When kept in closed vessels mouldiness 

 often occurs. If this be in groups it is collected with facility 

 at the end of a splinter of wood and removed, or the whole 

 fluid may be poured through a wet plug of cotton in the neck 



