RULES FOR APPLYING THE CAUTERY. 165 



the manner in wliieli it must be moved on the skin, is to be deter- 

 mined by the steps of the operation. In beginning the markings 

 of the firing or the initial drawing, the iron must be of a dark red 

 color, just hot enough to burn the thin coat of hair left on the 

 skin. By this method, any u-regularity in the drawing can be re- 

 moved and corrected by the passing of a second instrument. 

 When the entire surface has been covered with the initial draw- 

 ings, and everything is correct, the heat of the cautery can be 

 shghtly and progressively increased as the operation approaches 

 the end. Tiio rapidity with which the instrument is moved over 

 a hne should vary inversely to the degree to which it is heated, the 

 thickness of the skin, the consistency of the subcutaneous tissues, 

 and also the stage of the operation. Generally, the movement of 

 the cautery should be accelerated when the heat is greatest, when 

 the sldn is thin, when the tissues underneath are hard, and when 

 the operation is nearly completed. 



Another important rule is not to apply too heavy a pressure 

 upon the cautery when moving it over the skin. A shght pressm-e 

 with a slow movemeat is harmless and even advantageous at the 

 beginning of the operation, or when the skin is thick, but it be- 

 comes dangerous under the opposite conditions when the heat of 

 the cautery is extreme. In such a case a true incision of the skin 

 may be the result. Fu-ing is essentially a bloodless operation 

 even when severely applied, but it is only by the careful observ- 

 ance of the above rules that hemorrhage during actual cauteriza- 

 tion can be avoided. Its appearance during the ojieration is, we 

 beheve, the result of inattention, and caused by too hastily raising 

 the heat of the instrument, or more often by excessive pressure 

 upon it. 



The observance or neglect of these rules will demonstrate the 

 difference between scientific and unscientific firing, and show that 

 while one is true scientific surgery, the other is simply burning 

 the skin. The first is applied by one who apjireciates the value 

 of the residts he hopes to reahze, while the other merely places a 

 hot iron in contact with the skin, quite ignorant of the good or 

 evil results which may follow the act. As the operation progresses, 

 changes take place vipon the lines, which give an indication of the 

 strength of the firing. These objective changes consist in a change 

 of color in the hues, and an accompanying exudation from the skin. 



In the first degree, or light firing, the Hues are not deep, and 



