174 THE PATHOLOGYOF THE TEETH. 



natural structure, were from one to two lines and a 

 half thick, and were entire and imperforate. The 

 water percolating the stratum in which this tooth 

 had lain, had found access to the cavity through the 

 porous texture of its walls, and had deposited on its 

 interior a thin ferruginous crust; but the cavity had 

 evidently been the result of some inflammatory and 

 ulcerative process in the original formative pulp of 

 the tooth, very analogous to the disease called 'spina 

 ventosa' iu bone." 



