HARDWICKE'S SCIENCE-GOSSIP. 



211 



THE STOEY OF A PIECE OF QUARTZ, 



By J. E. TAYLOR, F.G.S., Etc. 



ACT," they say, "is 

 often stranger than 

 fiction." I do not 

 think you will find 

 this old saw better 

 illustrated in the 

 whole series of geo- 

 logical teachings than iu my 

 own history. That history is 

 connected with one of the 

 grandest discoveries of late 

 years, inasmuch as it carries 

 back the antiquity of the globe 

 far beyond the mighty ages 

 which had already been claimed 

 for it. Indeed, the practical 

 effect of this is to show the 

 geologist that time, as a factor, 

 has nothing to do with his in- 

 vestigations. That simple re- 

 lation in the succession of events is all he can 

 safely arrive at ; and that his finite mind can no 

 more conceive of the myriads of years which are 

 included in the world's biography, than it can 

 sum up in human arithmetic the stars and systems 

 which crowd the illimitable realms of space ! With- 

 in the last ten years a clearer geological knowledge 

 of my origin has caused geologists almost to double 

 the already great antiquity of the earth. At the 

 time I mention, or thereabout, it was usually under- 

 stood that the Cambrian period was the oldest and 

 most primeval. The human mind is essentially 

 conservative, and although geologists reasonably 

 claim to be more catholic than most men, they are 

 under the same influences. This is indicated by 

 their unwillingness to make the world appear older 

 than they possibly could help. Hence such terms 

 as "Primary," " Primordial," &c. applied to the 

 ancient strata— which nevertheless are all much 

 younger than myself— are so many landmarks which 

 have shown this tendency in the human mind. It 



may be, that although 

 No. 83. 



the geological formation to 



which I belong is undoubtedly the oldest known 

 formation, subsequent research may eventually 

 make known an older period still. The difficulty 

 in doing so, however, will be considerably height- 

 ened by the fact of all these oldest rocks having 

 passed through many changes, by heat and 'chemi- 

 cal action, so that nearly all traces of their former 

 fossils are effaced, and thus they are reduced to a 

 similarity of mineral condition all the world over. 



There are few of my readers who are not ac- 

 quainted with my general appearance. They have 

 gathered me as a milk-white pebble by the sea 

 beach, or have admired me as they climbed the 

 Scotch mountains and saw me sticking out of the 

 contorted rocks like a huge white rib. Or, they may 

 have been more pleased still with the geometrical 

 shapes which my substance is capable of assuming 

 as a six-sided, pointed crystal. It is of my former 

 condition, rather than of my latter, that I intend 

 now more particularly to speak. And yet it is 

 necessary for me to say that there are two common 

 conditions in which I am usually to be found. One 

 is as Quartz, the other as Quartzite. These terms 

 are merely significant of appearance, and include 

 little or nothing of chemical difference. Quartz pro- 

 per is usually found in veins, having been forced into 

 fissures when it was in a soft, heated condition. 

 Quartzite has not so completely lost all its original 

 structure, and its particles or grains may often be 

 seen retaining their original water-worn form. Again, 

 Quartzite does not occur as an intrusive rock, but 

 in huge stratified masses, hundreds of feet in 

 thickness. And yet you may find transitions in 

 these two extreme states of my family — even from 

 the transparent crystal condition of the " Brazilian 

 pebbles " to the coarse-grained and resinous appear- 

 ance of quartzite. 



Let me be thoroughly understood. Although I 

 am representing that great, and at present oldest 

 epoch in our planet's history — the Lavrentian—1 

 should not like you to fall into the mistake of sup- 

 posing that I am limited to it alone. On the con- 



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