VALENTIN S DISSECTING KNIFE. Ito 



spleen, kidney, &c., the double-bladed knife, the invention 

 of Professor Valentin, may be used with advantage. An- 

 improved construction of this knife, by Professor Quekett, 

 is represented in fig. 64. It consists 

 of two blades, one of which is pro- 

 longed by a flat piece of steel to form 

 a handle, and has two pieces of wood 

 riveted to it, for the purpose of its 

 being held more steadily; to this 

 blade another one is attached by a 

 screw; this last is also lengthened 

 by a shorter piece of steel, and both 

 it and the preceding have slits cut 

 out in them exactly opposite to each 

 other, up and down which slit a 

 rivet with two heads is made to 

 slide, for the purpose either of allow- 

 ing the blades to be widely separated 

 or brought so closely together as to 

 touch. One head of this rivet, being 

 smaller than the hole in the end of 

 the slit, can be drawn through it ; so 

 that the blade seen in the front of 

 the figure may be turned away from 

 the other in order to be sharpened, 

 or allow of the section made by it 

 being taken away from between the 

 blades. The blades are so con- 

 structed that their opposed surfaces 

 are either flat or very slightly con- 

 cave, that they may fit accurately 

 to each other, which is effected more 

 completely by a steadying pin, seen 

 at the base of the front blade. When 

 the instrument is required to be used, Fi s- 64 - 



the thickness of the section about to be made will depend 

 upon the distance the blades are apart : and this is regu- 

 lated by sliding up or down the rivet, as the blades, by 

 their own elasticity, will always spring open and keep the 

 rivet in place ; a cut is then to be made by it, as with 

 an ordinary knife, ind the part cut will be found between 



