32 LANDMARKS MEDICAL AND SURGICAL. 



bladder a stone as large as a hen's egg. The stone, the knife, 

 and the portrait of the operator, may be seen to this day in 

 the museum at Leyden. 



65. Division of Aorta. The aorta generally divides 

 at a point one inch and a half below the umbilicus. A 

 more reliable guide to this division than the umbilicus, is a 

 point (a very little to the left) of the middle line about the 

 level of the highest part of the crest of the ilium. A line 

 drawn with a slight curve outwards from this point to the groin, 

 where the pulsation of the common femoral can be distinctly 

 felt (rather nearer to the pubes than the ilium), gives the 

 direction of the common iliac and external iliac arteries. 

 About the first two inches of this line belong to the common 

 iliac, the remainder to the external. Slight pressure readily 

 detects the pulsation of the external iliac above ' Poupart's 

 ligament.' 



As a rule, the length of the common iliac is about two 

 inches, but it should be remembered there are frequent 

 deviations. It may be between three-quarters of an inch and 

 three inches and a half long. These varieties may arise either 

 from a high division of the aorta, or a low division of the 

 common iliac, or both. It is impossible to ascertain during 

 life what is its length in a given instance, for there is no 

 necessary relation between its length and the height of the 

 stature. It is often short in tall men, and vice versA. Ana- 

 tomists generally describe the right as a trifle longer than 

 the left ; but their average length is pretty nearly the 

 same. 



66. Mr. Abernethy, who in the year 1796 first put a ligature 

 round the external iliac, made his incision in the line of 

 the artery. But the easiest and safest way to reach the vessel 

 is by an incision (recommended in the first instance by Sir 

 Astley Cooper, and now generally adopted), beginning just 

 on the inner side of the artery, a little above Poupart's 

 ligament, and continued upwards and outwards a little 

 beyond the spine of the ilium. The same incision extended 

 farther in the same direction would reach the common 

 iliac. 



