6o6 Veterinary Obstetrics 



amputated and then drawn back and forth in a sawing man- 

 ner. They are effective in their work and in some cases offer 

 special advantages, but on the whole they have not come into 

 general use. They are comparatively expensive, rather difficult 

 to apply, are not very rapid in execution, and are exceedingly 

 difficult to maintain in aseptic and working condition. 



Stiff-handled obstetric saws are also recommended by some 

 practitioners. Short finger saws, with short handle and finger- 

 ring like c, Fig. 103, are recommended by some, but they have 

 little efficiency in most cases because wholly dependent upon the 

 inserted hand, tightly compressed and largely powerless, for an5' 

 use. Ivong handled saws are more workable because the saw can 

 be guarded with the inserted hand and the force applied with 

 the free hand. They can be used in no operation and applied to 

 no part for which the obstetric chisel is not equally efficient and 

 safe. We have repeatedly attempted the use of chain-saws, 

 sectors, and stiff handled saws, and have always laid them aside 

 as greatly inferior to chisels. 



Obstetric Chisels. The simplest and most effective imple- 

 ment for section of fetal bones is the embryotomy chisel, which, 

 like other instruments, is constructed in a variety of forms. We 

 use a chisel. Fig. 106 d, made of the best steel, of J^ or ^ inch 

 diameter, and about 30 inches in length, with the chisel end 

 about 2 inches wide and tapering gradually backward toward the 

 handle for a distance of 4 or 5 inches. The chisel blade is about 

 tV to % in. thick, so that it may safely pass through the hardest 

 bone in the fetal body, and the cutting edge of the chisel is made 

 slightly concave in order to render it less liable to slip to one side. 



Such a chisel is readily kept in order and is easily applied by 

 the operator to any portion of the fetus which is within his 

 reach. Grasping the chisel blade in his hand, he carries it to 

 the part to be operated upon and, placing the instrument in the 

 best direction possible, against the part, he instructs an assistant 

 to drive it through the tissue with a mallet or hammer. When 

 driving the instrument through bone, it should be forced but a 

 short distance at a time, then loosened and perhaps revolved on 

 its long axis in order to pry the bones apart and also to avoid 

 driving the chisel too far and having it become caught in such a 

 way that it is difficult to remove it. 



In amputating a limb, the chisel should not be placed upon its 



