58 LYELL'S ELEMENTS OF GEOLOGY. 



Mineralization of Organic Remains. 



Another accidental experiment has been recorded by Mr. Pepys 

 in the Geological Transactions.* An earthen pitcher containing 

 several quarts of sulphate of iron had remained undisturbed and 

 unnoticed for about a twelvemonth in the laboratory. At the end 

 of this time when the liquor was examined an oily appearance 

 was observed on the surface, and a yellowish powder, which 

 proved to be sulphur, together with a quantity of small hairs. 

 At the bottom were discovered the bones of several mice in a 

 sediment consisting of small grains of pyrites, others of sulphur, 

 others of crystallized green sulphate of iron, and a black muddy 

 oxide of iron. It was evident that some mice had accidentally 

 been drowned in the fluid, and by the mutual action of the animal 

 matter and the sulphate of iron on each other, the metallic sul- 

 phate had been deprived of its oxygen ; hence the pyrites and the 

 other compounds were thrown down. Although the mice were 

 not fossilized, or turned into pyrites, the phenomenon shows how 

 mineral waters, charged with sulphate of iron, may be deoxy- 

 dated on coming in contact with animal matter undergoing putre- 

 faction, so that atom after atom of pyrites may be precipitated, 

 and ready, under favourable circumstances, to replace the oxy- 

 gen, hydrogen, and carbon into which the original body would 

 be resolved. 



The late Dr. Turner observes, that when mineral matter is in 

 a " nascent state," that is to say, just liberated from a previous 

 state of chemical combination, it is most ready to unite with 

 other matter, and form a new chemical compound. Probably 

 the particles or atoms just set free are of extreme minuteness, 

 and therefore move more freely, and are more ready to obey any 

 impulse of chemical affinity. Whatever be the cause, it clearly 

 follows, as before stated, that where organic matter newly imbed- 

 ded in sediment is decomposing, there will chemical changes 

 take place most actively. 



An analysis was lately made of the water which was flowing 

 off from the rich mud deposited by the Hooghly river in the 

 Delta of the Ganges after the annual inundation. This water 

 was found to be highly charged with carbonic acid gas holding 

 lime in solution.f Now if newly deposited mud is thus proved 

 to be permeated by mineral matter in a state of solution, it is not 

 difficult to perceive that decomposing organic bodies, naturally 

 imbedded in sediment, may as readily become petrified as the 

 substances artificially immersed by Professor Goppert in various 

 fluid mixtures. 



* Vol. i. p. 399, first series. 



t Piddinglon, Asiat. Researches, vol. xviii. p. 226. 



