98 MR GOODSIR ON MUSKET-BULLETS FOUND IN THE TUSKS OF THE ELEPHANT. 



under the hole may be strengthened by the formation of new substance. When 

 the ball is detained by the ivory, but penetrates so far as to wound the pulp, the 

 latter ossifies round it, and the ossified portion sooner or later becomes enveloped 

 in new ivory. If the ball penetrates the pulp, the latter ossifies round it, and be- 

 comes attached to the hole in the ivory. If the tusk is growing rapidly, and the 

 nucleus of pulp-bone does not speedily adhere to it, the ball will ultimately be 

 situated above the hole. The ball may also pass across the pulp, and become at 

 last enveloped, along with its bony envelope, in the ivory of the opposite wall. 



Second, In the second class of wounds, in which the ball enters the pulp-ca- 

 vity through the socket and side of the tusk, the consequent changes seem to be the 

 following : first, ossification of the pulp surrounding the ball, and the ultimate appli- 

 cation of the mass to the hole in the ivory, and, as the latter is necessarily at this 

 part of its extent very thin, the hole is closed ; second, the application to the hole 

 in the ivory, and to the surface of the ossified pulp in it, of cement formed by the 

 internal surface of the tusk-follicle. For although the ball may have removed or 

 at least torn the follicle opposite the hole in the ivory, yet, as the tooth advances 

 in the socket, the ball will in time arrive at a sound portion of the latter. There 

 is a specimen on the table which proves that the wounded portion of the follicle 

 may perform this duty sufficiently well. In this specimen the external surface of 

 the cement exhibits a longitudinal fissure, with smooth rounded edges, resulting 

 from the defective formation of cement in the situation of a longitudinal rent or 

 wound in the membrane of the follicle, through which the ball had entered the 

 ivory. The hole in the ivory then being plugged up externally by cement, and 

 internally by ossified pulp, the case proceeds as in the last class of wounds, the 

 ossified portion of the pulp surrounding the ball becoming inclosed in true ivory. 



Third, When the foreign body enters from above, without wounding the tusk, 

 the pulp ossifies round it, and true ivory envelopes the mass, in the usual manner. 

 I have not seen any morbid ivory which could be referred to wounds of the class 

 now under consideration ; but a very interesting account is given by Mr COMB, in 

 the Philosophical Transactions,* of a tusk in which a spear-head was found, and 

 which could only have entered the cavity from the base of the pulp. Mr COMB 

 describes and figures the ossified portion of the pulp, and the manner in which it 

 had attached itself to the ivory, and become covered by it, so as to obliterate par- 

 tially, and to alter the relative width of the pulp-cavity. 



The description I have now given of the changes which ensue on wounds of the 

 tusks of the elephant, explains many curious appearances in ivory, and the difficul- 

 ties anatomists and physiologists have had in understanding them. It explains 

 the drawings and descriptions of KLOCKNER, RUYSCH, and CAMPER; does away 

 with the necessity of supposing, with BLUMENBACH, that true ivory is regenerated, 



* Phil. Trans. 1801. 



