52 Volatile Oils. 



tities ten times as great as strictly required for dissolving all 

 the gold. I suppose that a sample of the pulverized quartz 

 has been previously tested, a thing which will be always 

 done. 



Assuming that rich quartz, after being deprived of its 

 coarse gold by sieving or sluicing, contains on an average one 

 and a-half or two ounces of gold to the ton in a state of almost 

 atomic division, the cost of chlorine, applied in quantity 

 forty fold greater than absolutely needed for its solution, will 

 be about two for every ton of quartz. 



The accounts of the loss of mercury in that process are 

 \ery variously stated at, from four ounces to one pound per 

 ton of quartz. Suppose a pound were lost, it would be in 

 value about two shillings. Now that would be about the 

 cost of the requisite amount of chlorine for such treatment 

 as that just described. 



It must never be forgotten, that scarcely one-tenth part of 

 the water used in the Chilian mill is required in this process 

 — making it available all the year round in dry places. 



It has sometimes been urged against chlorine, that it is a 

 deleterious agent, but when we remember the extensive use 

 made of it in Great Britain, for the purposes of bleaching, 

 such an objection ceases to be heeded. 



Art. XVT. — Abstract of a Paper on the Yield and Uses of 

 Volatile Oils, from Native and Imported Plants, in the 

 Colony of Victoria. By J. Bosisto, Esq. 



Having paid considerable attention to the medicinal 

 plants of Victoria and their products, and of late more 

 particularly to those producing Volatile Oils, I am induced 

 to lay before this Society my notes and observations upon 

 some of the latter, and also to direct attention to the pro- 

 bable advantages of cultivating European plants which 

 produce Volatile Oils. 



The term " oils " applied to products of this nature often 

 conveys a wrong impression, few persons calling to mind the 

 distinctive characteristic expressed by the term " essential " 

 or " volatile." A true Volatile Oil leaves behind no trace of 

 grease when dropped on the finest fabric, nor does it injure 

 the most delicate colour. Such are, with one exception, the 

 Essential Oils in question. 



