Chalk and Flint Formation. 29 



this circumstance. Professor Sir William Thomson, 

 however, when President of the British Association 

 in its meeting at Edinburgh in 1871, went so far as 

 to suggest that even seeds of life might have come 

 from a meteoric source extraneous to this earth. 



But apart from theories, we are dealing with the 

 evidence of facts. The flint has in very numerous 

 cases moulded itself into organic forms, partly of 

 the sea, partly of the land ; and this has manifestly 

 not been from any special aptitude of the flint for 

 organic attraction or substitution. How then are 

 these forms to be accounted for ? 



Now in some cases the answer is plainly furnished 

 by the facts themselves. The galerites and various 

 other echinites are found imbedded in circumfluent 

 flint, which has found an entrance into the shell by 

 an orifice and has filled it, thus moulding itself into 

 the form. So also with lobster-claws, and similar 

 objects of the sea-shore. In regard to the vegetable 

 forms the case requires a little more careful con- 

 sideration ; but they also will be found to give of 

 themselves a reasonable explanation of their origin. 

 They consist of decayed and dried tree-roots or 

 broken branches ; or of vegetable roots or fruits 

 which had been lying for the most part covered by 

 the soil with a part protruding. The molten flint, 

 falling as liquid fire upon the ground, has apparently 

 burned off the protruding part, and has then eaten 

 its burning way into the tinder of the rotten tree- 

 root wherever it was not bounded by the incom- 

 bustible soil in which it lay. And the same with 

 old dry vegetables, often eaten out by worms and 

 filled with soil, or pods and fruits which have fallen 

 and become covered with soil, leaving only a small 

 part protruding sufficient for the fiery fluid of the 



