CAUTERISATION. 155 



Chloride of antimony, otherwise known as butter of antimony, 

 has a powerful action, and produces a whitish, at first soft and 

 afterwards hard, sharply defined scab. 



Chloride of zinc is an energetic caustic, and may advantageously 

 be used by mixing one part zinc chloride with one to four parts of 

 flour, water being added to form a paste. 



Nitrate of silver and sulphate of copper are perhaps the caustics 

 most generally employed. Nitrate of silver, or lunar caustic, has 

 only a superficial action. The scab is at first white and soft, later 

 becoming dark under the action of light. Sulphate of copper is 

 cheaper than lunar caustic, and is sometimes used to destroy 

 exuberant granulations. 



The longer the caustic remains in contact with the tissues the 

 more extended is its action, as it continues to spread from the fresh 

 scab. Where the action proves insufficient it may be renewed as 

 soon as the scab is shed. For destroying new growths, caustics 

 in the form of pastilles or rods are sometimes used, an incision being 

 made in the growth for their introduction. In other cases solutions 

 are injected. These methods, however, are not to be commended 

 because the range of action of the caustic cannot be controlled. 

 Sometimes a portion of the growth is left, necessitating a second 

 operation ; sometimes the action of the caustic extends to healthy 

 tissue with unfortunate results. The caustics, and especially the 

 more active, produce severe and continued pain during their action. 



The actual Cautery— Firing. Although less used than formerly 

 firing continues very popular, and is employed with success in many 

 conditions which have resisted all other treatment. Without doubt 

 it gives lively pain, necessitates a certain period of rest, and some- 

 times leaves indelible marks, but these drawbacks are more than 

 counterbalanced by its many advantages. Among the indications 

 for the employment of the actual cautery, the most frequent are 

 chronic affections of tendons, tendon sheaths, ligaments, bones, 

 synovitis, sprains, luxations, exostoses, enlarged joints, and necrosis. 

 Tt is also used to divide tissues, to remove chronic lymphatic 

 thickening, to stimulate healing of fistula?, indolent ulcers, and 

 poisoned wounds, in the treatment of tumours, and to check 

 haemorrhage. Distinctions have been made between mediate and 

 immediate, superficial and deep or penetrating firing. In mediate 

 cauterisation, a glowing iron is brought close to the spot to be acted 

 on so that the parts are merely heated by radiation ; in immediate 

 cauterisation, the instrument is brought in actual contact with 

 the tissues. Surface firing, i.e., firing extended areas all over, 



