1818.) ON THE FORMATION OF ROCKS. 265 



After shaving off all that we supposed to be formed 

 by fire, the next active agent that would attract our at- 

 tention would be water. The productions and changes 

 wrought by the operation of this agent, would be ex- 

 amined: the aggregates of rounded particles, deposition 

 with organic matter, &c. would be considered as belong- 

 ing to formations by water. 



Clearing the surface of the ball with our dissecting' 

 chisel of all that we could ascertain by analogy to belong 

 to the formation by water, or fire, we would come to a 

 species of matter that did not exactly resemble either of 

 the above formations, which, on examining, we would find 

 of various textures; and comparing it with the portions al- 

 ready cut off, we would find part of this matter which had 

 a distinct resemblance to that formed by fire, and part to 

 tliat formed by water, but so mixed and confused to- 

 gether as to prevent our forming any distinct conclusions. 

 After turning the ball two or three times, we would na- 

 turally wish to know ^vhat constituted the interior or cen- 

 tral part; for which purpose we would cut it in two, and 

 expose the interior to our examination and analysis, as we 

 had before examined the exterior; and if we should find 

 that the interior was fluid, and like a soft boiled e^g, and 

 only the exterior was solid, we might follow the analogy 

 of the |gg a little farther, and deduce the probability, that 

 at some former period the exterior crust had been fluid, 

 and had since become solid, by some operation of nature 

 analogous to something we had ourselves observed. 



On the contrary, should the examination of the inte- 

 rior of the ball, prove, that it consisted of a variety of so- 

 lid substances, farther and farther removed from any re- 

 semblance with those w% had observed as formed on the 



