1 1 8 Anatomy Applied to Medicine and Surge? y. 



nent ridge the "angulus Ludovici" which corresponds 

 to (a) the junction of the second costal cartilages with the 

 sternum ; (b) the arch of the aorta ; (c) the bifurcation of 

 the trachea ; (d) the meeting point of the anterior borders 

 of the right and left lungs ; (e) the middle of the fifth dor- 

 sal vertebra; (f) about the upper limit of the pericardium 

 and the lower limit of the superior mediastinum. The 

 lower border of the gladiolus, i.e., the junction of the gladi- 

 olus and the ensiform cartilage, is on a level with the disk 

 between the ninth and tenth dorsal vertebrae. The ribs, 

 twelve in number, pass in a curved manner obliquely 

 downwards and forwards. The extent of this obliquity 

 reaches its maximum at the ninth and decreases from this 

 to the twelfth rib, and is such, that the anterior end of 

 one rib is about on a level with the head of the fourth rib 

 below thus the second is on the same level as the head of 

 the sixth rib, the third, as that of the seventh, etc. The 

 ribs increase in length from the first to the seventh, below 

 which they decrease to the twelfth, whereas they decrease 

 in breadth from the first downwards. Lastly, they are 

 elastic, mobile arches, and the degree of mobility increases 

 from the first to the eleventh, which, with the twelfth, are 

 very mobile. The intercostal spaces are wider in front 

 than behind, and the first three are widest of all. Rules 

 } for counting the ribs. In front, the simplest and most 

 trustworthy method is to establish the situation of -the se- 

 cond rib by feeling for the ridge of junction of the manu- 

 brium and gladiolus, which corresponds to this rib, and 

 then count downwards. This may be confirmed by feel- 

 ing for the twelfth or lowest rib, at the same time bearing 

 in mind that this may be rudimentary, and then, count- 

 ing from it upwards. The seventh can be recognized by 

 its being the last to articulate with the sternum, while the 

 nipple, in the male, lies between the fourth and fifth ribs, 



