Dec. 1, 1870.] 



HARDWICKE'S SC IEN CE-GOS SIP. 



26c 



THE STOEY OF A PIECE OF SANDSTONE. 



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



IKE my miuera- 

 logical acquain- 

 tance, the piece 

 of limestone, 

 generally I am 

 about to do duty 

 for a group of 

 individuals com- 

 ^ mon to every 

 geological lormatiou. But 

 each of us has a separate 

 story to tell, and I shall find 

 it quite sufficient to bring all 

 the circumstances of the epoch 

 in which I lived, sufficiently 

 clear to my own recollection. 

 It is said that a number of 

 people, calliug them selves spiri- 

 tualists, \r\xo live in the present 

 period (so far removed in time 

 from mine), profess to be able 

 to interrogate a piece of lime- 

 stone or sandstone, and to get 

 its story in some easier way than by the ordinary 

 cross-questioning of science ! All I can say is, I wish 

 the events of my own life were so permeated in my 

 substance. If this theory be true, the modern 

 science of geology will have to give up induction, 

 and fling itself into the arms of the spirit rappers ! 



Every one of my listeners knows what a piece of 

 sandstone is like. There is no need for me to de- 

 scribe my appearance, therefore, as novelists do their 

 heroes. But how many thus familiar are aware 

 that in ninety-nine cases out of a hundred, every 

 such piece of sandstone was originally formed along 

 the floor of old oceans ? Those ocean-bottoms are 

 now represented by dry-land surfaces, where the 

 vegetation luxuriates on the mineral substances accu- 

 mulated under such widely different circumstances. 

 Even where no marine organic remains are present, 

 as fossils, to prove the marine origin of the sand- 

 stones, that origin is none the less certain. I can- 

 No. 72. 



not speak with certainty as to the nature and ex- 

 tent of the dry lands and continents of the epoch in 

 which I was born. Suffice it to say they must have 

 been great, for the rivers which watered them were 

 large, and brought great quantities of mud and 

 sand down to the sea. The ocean currents and tides 

 also wore away the coast-line, and added to the 

 quantity of loose sand and mud which accumulated 

 under the waves in consequence. Thus it was that 

 I was born. 



My earliest remembrances are of my lying loose 

 and unconsolidated on the ocean-floor, and of con- 

 stant additions being made to the sheet of which I 

 formed part. It was whilst I was lying in this 

 state, as so much ordinary sand, that I received my 

 impressions of what was going on around me. 

 These consisted of a familiarity with the commoner 

 animals which lived in the sea, or with occasional 

 plants and vegetables which had been carried there 

 by rivers, until they sank to rest in my bosom when 

 they had arrived at a water-logged condition. Of 

 these I will speak presently. Meantime let me 

 make a few remarks as to the changes which trans- 

 posed me from loose marine sand into hard sand- 

 stone. And in doing so, it will be evident that the 

 same explanations will answer for the similar alter- 

 ation of sandstone rocks, both of earlier and later 

 geological periods. , 



The sand or mud brought down and laid on the 

 sea-floor in the manner I have mentioned, was not 

 of an absolutely pure character as regards its min- 

 eral composition. That is to say, it was not all 

 silica, or alumina, as the case might be. In all in- 

 stances the material was mixed with more or less 

 of iron rust, or of lime, and free silica. The two 

 latter acted as cementing pastes to those sandstone 

 rocks which are now of a lightish colour ; whilst 

 the iron was the compacting agent with such dark 

 red rocks as that of which I form part. Indeed, in 

 most cases, even when the sandstone is of a light 

 yellow, a small percentage of iron has gone a great 

 way towards binding the loose grains of sand 



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