Aug. 1, 1870.1 



HARDWICKE'S SCIEN CE-GO S S IP. 



1C9 



THE STOEY OP A PIECE OP GEANITE. 



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



^fHERE are few 

 rock substances 

 on the surface 

 of the globe 

 which have re- 

 ceived more dis- 

 cussion and been 

 more investi- 

 gated thanjnyself. I am some- 

 what proud of the attention I 

 have received in this respect, 

 for most of the leading geolo- 

 gists of every country, for the 

 last century, have devoted 

 themselves to the task of seek- 

 ing out my antecedents. I am 

 acquainted with a whole library 

 of books, all most learnedly 

 written, and various of them 

 proving the reverse of the 

 other, which have been penned on this inexhaus- 

 tible subject. Even yet the question can hardly be 

 regarded as finally settled. Every now and then 

 some moot point or another crops up to engage the 

 attention of philosophers, but, thanks to the progress 

 of other sciences, the investigation of these is no 

 longer confined to verbal expressions. It is not 

 a little amusing to remember the hot discussions 

 which were held over me at the beginning of the 

 present century. Philosophers though they profes- 

 sed to be, the disputants resembled political squab- 

 blers more than anything else. One set declared I 

 was bom amid fire, — the other that I was of purely 

 watery origin. Each believed in their own ipse 

 dixit, and, as nothing could be absolutely proved, 

 backed their own opinions by personalities. Some- 

 how or other the former sect, who were called 

 Plutonists, got the better of the latter, who were 

 termed Neptunists. (The origin of these phrases 

 my readers will not find it difficult to understand.) 

 But my Plutonic commentators carried their victory 

 too far. Not content with proving that I was not 

 No. 68. 



a mere aqueous rock, they proceeded to declare 

 I was nothing more nor less than one which had 

 cooled down from a fused condition, something like 

 iron slag ; nay, it was even urged that I was older 

 than any other rock, and the theorists mapped out 

 an idea— which existed for many years after, chiefly 

 owing to its remarkable novelty — showing how the 

 whole universe was formerly one great cosmical fog ; 

 that this diffused matter was condensed into suns, 

 planets, and satellites, each of which existed for ages 

 in a molten condition, owing to the heat evolved 

 during the process of condensation ; that the ex- 

 terior of each planet cooled during the time which 

 followed, and that granite formed part, or whole 

 of this cooled envelope ! Such in brief was the 

 orthodox notion of my birth, little more than a 

 quarter of a century ago. 



Shall I enlighten my readers a little as to the 

 nature of my mineralogical composition? I feel 

 sure that most of them are acquainted with it 

 already, but, if only for. form's sake, I must go 

 through with it again. My name is of Latin deriva- 

 tion, and was given me on account of the granular 

 character presented by my different minerals. Gene- 

 rally speaking, these are four in number— Quartz, 

 Felspar, Mica, and Hornblende. Very frequently 

 there are also traces of other minerals ; but these are 

 the commonest, and those in fact which make up my 

 bulk. The Quartz portion you may tell by its glassy 

 appearance, and usually milk-white colour ; whilst 

 another good test is its superior hardness. This 

 mineral is almost pure silica, and is one of the most 

 refrangible of known substances. It can with diffi- 

 culty be slightly dissolved in hot water, under 

 great pressure ; whilst it requires a great deal of 

 heat to melt it, and, generally speaking, some sort of 

 flux to set it a-going. Next most abundant mineral 

 in the constitution of myself and relatives (for our 

 name is Legion) is that called Felspar. Your eye 

 may detect it in any mass, by its pink or flesh- 

 colour, whilst it is so soft that you may scratch it 

 with your finger nail. It is owing to the unusual 



