HIPPOPOTAMUS TEETH OR TUSKS. 275 



enamel is removed by the aid of a chisel and grindstone, or, more frequently, 

 by steeping the tusks or sections thereof, in a solution of muriatic acid, 

 sufficiently long to destroy the enamel, without affecting the dentine ; the 

 softer parts, at the same time, being coated or painted over with some fatty 

 substance, to preserve them from injury during the operation. Sometimes 

 the blowpipe is resorted to as a means for removing the enamel, and a fine 

 file is afterwards used in either case, for imparting the final surface to the 

 bone. The points of the canines are generally defective, and in the process 

 of working are first removed, the tusks being afterwards sawn into transverse 

 sections, of varying thickness, according to the destined application, and as 

 required by the operator. 



Although the teeth of the hippopotamus are all but monopolised by 

 dentists, yet the very excellent quality of their dentine is more widely 

 appreciated, and likewise adopted for a few other purposes in the arts. 

 When great delicacy is required, this bone is found more suitable for 

 carvings, than the ivory of the elephant, and is much used in France for 

 this purpose, especially in the manufacture of fine brooches. 



The handles of surgical instruments are sometimes formed of this 

 material, for which purpose it is admirably adapted, because of its being less 

 liable to receive stains than other sorts of ivory. 



Vases made of hippopotamus tusks were displayed in the Great Exhibi- 

 tion of 1851 ; and in the Irish Exhibition, a Mr R. Barter, of Dublin, exhi- 

 bited some elegant intaglio brooches, consisting of figures carved in the same 

 substance, and mounted on a groundwork or surface of cornelian. The 

 enduring nature of the hippopotamus ivory appears to have been known, 

 and valued, as early as the first century ; for, according to a writer named 

 Pausanias, a certain Greek statue of " Dindymene " had its face "formed of 

 these teeth, instead of elephant ivory." 



A few words on the incisor teeth of the hippopotamus received into 

 commerce, will suffice. They are not so generally imported as the canines, 

 with the exception of the two lower, lateral, and projecting incisors, 

 commonly called tusks in the market, as distinguished from the canines, 

 which are usually termed teeth. These projecting incisor teeth, as already 

 described, are long, straight, and hollow for a portion of their length, like 

 the canines ; but differing vastly in quality from the latter, being consider- 

 ably softer, and more easily affected by the fluids of the mouth, so that they 

 are seldom used by dentists. Yet these long, straight teeth have their 

 especial application, being employed in the manufacture of the long 

 knitting needles, and netting meshes, used by ladies, as well as for other 

 more general purposes. The enamel on these lateral teeth appears to be 

 confined to the projecting point, and does not extend into the jaw. 



The smaller and curved incisors of the upper jaw are comparatively 

 valueless, except for common turnery work. 



I may here mention, that unless the teeth of the hippopotamus are 

 employed by the dentist, the enamel is always removed ; and generally by 

 means of an acid bath, as no ordinary tool produces any effect upon it. 



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