APPLICATIONS OF F1RINO. 



157 



the inequalities of the surface and to ensure each part being subjected 

 to the same action. Fig. 210 shows the ordinary form of the English 

 firing iron. It is suitable for most purposes. The length of stem 

 varies according to whether it is intended for use on the animal in 

 a standing position or when cast. Messrs. Arnold make these instru- 

 ments in many forms, all fitting one handle. The head of the point 

 or bud-firing iron consists of a more or less elongated cone ; for deep 

 firing it is drawn to a much finer point. Needle firing is performed 

 with very fine points, capable of penetrating the tissues deeply. It 

 was formerly the custom to use stout needles, about four inches 

 in length, which were brought to a red heat in a charcoal furnace, 



Fig. 214. — Degive's apparatus ready for action. The reservoir in the 

 handle is filled with sponge saturated with benzine vapour. The bellows 

 pumps air through this reservoir. The stream of benzine-laden air is 

 mixed with a stream of pure air controlled by the two-way tap at the 

 base of the handle, and burns with an intensely hot blue flame in the 

 hood. The tap at the base of the handle regulates the size of the name, 

 and therefore the temperature. 



grasped with pincers or forceps and plunged into the tissues. These 

 were replaced by instruments consisting of a heavy cone-shaped head, 

 with a central aperture through which a suitable needle could be 

 passed. The head was first heated, and when red, the needle was 

 dropped into position. In the greater number of such instruments, 

 however, the needles become cold very rapidly, and the large head 

 cauterises the skin around the perforation. To protect the skin it 

 becomes necessary to place a small disc of iron with a central 

 aperture over the point of operation. Several instruments with 

 movable needles have been invented. Degive's (Figs. 213 and 214) 

 is probably the best, though similar instruments have been produced 

 by Bourget and De Place. It consists of a handle, which also acts 



