404: APPENDIX. 



history of the country, and calculated to lead to conclusions so 

 important to the science of geology, that I am anxious to avail 

 myself of your concurrent testimony as to the fact of the exist- 

 ence of the tree in a mineralized state, and the natural appearances 

 of the spot where it lies imbedded. I feel the more solicitude on 

 this subject, as I am aware that any description of this pheno- 

 menon which I may be induced to communicate to the public, 

 will be received with a degree of caution and scrutiny which it is 

 the province of the naturalist to exercise whenever any discovery 

 is announced affecting the existing theories of the natural sciences, 

 or tending to increase the volume of facts upon which their ad- 

 vancement and perfection depend. I am aware, also, that what- 

 ever degree of caution and vigilance it may be proper to exercise 

 to prevent errors from mingling with the sound doctrines of the 

 physical and other sciences, still more care and circumspection is 

 requisite in examining facts which affect the progress of geology." 

 I quote an extract from Governor Cass's reply on the subject : — 

 "The appearance of the wood and bark indicates that it was a 

 black walnut, the juglans nigra of our forests. We computed its 

 original diameter, at the place where it is concealed in the earth, 

 to have been three feet, and at the other end eighteen inches. 

 The texture of the wood, and the bark and knots, are nearly as 

 distinct as in the living subject, and the process of decay had not 

 commenced previous to the commencement of this wonderful con- 

 version. Every part of the mass which we could examine is 

 solid stone, and readily yields fire by the collision with steel. 



" When we visited the spot, the water of the river was at the 

 lowest stage ; but there was no part of the tree within some 

 inches of the surface. The rocky bed of the stream was formed 

 round and upon it. We raised from it pieces of the rock, which 

 were evidently in situ, and which had been formed upon the tree 

 posterior to the period of its deposit in its present situation. This 

 rock is a species of sandstone, whose characteristic features must 

 be well known to you. 



"There are no mineralized substances of vegetable origin in the 

 vicinity of this specimen, nor are there any appearances which 

 indicate that its present condition has been caused by any pecu- 

 liar property in the waters of the Des Plaines." 



