APPENDIX. 143 



This has been, exceptionally, controverted; it has been held that the 

 mineral seams, variously denominated according to their thickness, were 

 originally cracks, subsequently filled by a process of deposition, for which 

 present experience and hypothetical science fail satisfactorily to account. 



The lode in question conclusively prostrates Mr. Evan Hopkin's theory 

 that auriferous quartz in situ, and its contained gold, is the result of electrical 

 action, or that in common with magnetic agency. 



Remote hypothesis _may postulate as an objection, rather than really con- 

 ceive, that the electrical or magnetic formation of the Laidlaw lode may 

 have been antecedent to its plastic state. 



But no one would credit or advocate such a notion unless he were intent 

 on establishing a favourite theory. 



Natural philosophers have natural feelings ; no one likes to be wrong in 

 a matter to which he is committed in writing. 



Quartz is crystalline, sometimes perfectly so, in common with volcanic 

 obsidian, and factitious glass, which it resembles. It is a flux of silica more 

 pure than glass or obsidian, which contain more alkaline fluxes, such as lime, 

 potash and soda ; but auriferous quartz, imperfectly crystallized, invariably 

 contains iron, which can be drawn from the pulverized mineral with a 

 magnet. 



The arrangement of crystalline particles is an illustration of a certain 

 kind of attraction ; but this attraction or affinity resides in the substance itself 5 

 it is only analogous to magnetic attraction; it has no peculiar sympathy with 

 external polar influence; it seems to have far more connection with chemical 

 affinity than atmospheric or terrestrial electricity. 



Were crystallization more than merely analogous to polar magnetism, in 

 the formation of ice we should observe that the arrangement of successive 

 atoms would follow or pursue some particular direction, but it is not the case ; 

 the acicular radiations from the point first congealed shoot out in all direc- 

 tions, and by interweaving eventually form a solid uniform mass of equal 

 thickness ; — a lake or pond, does not as a rule, freeze from one quarter of 

 the compass to another. 



Still less can electricity or magnetism account for the presence of metals 

 in ores; rare specimens of crystallized gold have been produced in nature — 

 in art crystals are produced by allowing substances to take their own form 

 after fusion or solution, and electricity, to produce the same result, must 

 either fuse or solve. 



If by this or other means electricity can accelerate the formation of a 

 crystal, it is merely as a local laboratory agent that it acts ; its use and action 

 in this respect as a natural agent, has neither been traced nor proved. 



An attempt to account for the presence of gold in the lode, seems to be 

 fraught with the same difficulties which would attend a similar investigation 

 with respect to other metals, and the minerals with which they are usually 

 associated. 



Most of them have affinities in themselves, and with one another. The pecu- 

 liar affinity which quartz has with gold has n«ver been displayed or explained 



