Mr. Le Gros Clark on the Mechanism of Respiration. 125 



He survived the injury less than three days, and there was complete para- 

 lysis of motion and loss of sensation below a line level with the nipples ; 

 the movement of the arms was also impaired. "The walls of the chest, 

 across and below the nipples, were retracted at each inspiration." I quote 

 the words of the Hospital Registrar; but I repeatedly proved this, and 

 demonstrated the fact to others, by placing around the chest, just over 

 the nipples, a tape, which became relaxed at each inspiration, to the ex- 

 tent of at least half an inch. The inspirations were short and sudden 

 the expirations prolonged, and latterly intermittent. This is not the only 

 instance in which I have observed this phenomenon under similar con- 

 ditions. 



The following case has more recently come under my observation, and 

 I give it according to the report of Mr. Anderson, the Surgical Regis- 

 trar of the hospital : — " F. F., aged 58, a bricklayer, was admitted into 

 St. Thomas's Hospital in February 1873, having fallen from a consider- 

 able height, and struck some projecting object in his descent ; he remained 

 incapable of movement, though perfectly sensible. The lower limbs were 

 paralyzed, and the movements of the upper extremities were impaired ; and 

 he complained of great pain shooting from the neck into the upper extre- 

 mities. In breathing, the whole chest was very perceptibly drawn in du- 

 ring inspiration, and the abdomen became more prominent than is normal. 

 The chest was slightly raised as a whole, and the sterno-mastoids were 

 seen to act strongly. The lower ribs were not drawn downwards, but 

 appeared to be pulled directly inwards, or inwards and slightly upwards. 

 In expiration the chest-walls appeared to relax, as if from the cessation of 

 some contracting influence. The respiration, as a whole, was jerking, but 

 not increased in frequency. Subsequently the chest appeared to act uni- 

 laterally, as if from unequal action of the two sides of the diaphragm, the 

 ribs on the left side being drawn inwards during inspiration, whilst the right 

 half of the thorax was thrust outwards passively. He survived the accident 

 about sixty hours ; and the cord was found crushed between the fifth and 

 sixth cervical vertebrae, which were fractured." 



This peculiarity in the diaphragmatic breathing must be due, in the 

 main, if not entirely, to the suspension of the intercostal action, whereby 

 the ribs are left at liberty to be acted upon, and thus drawn in by the 

 contraction of the diaphragm. 



13. I would remark, as bearing upon the foregoing observations and 

 those I am about to make, that in the unfettered adult body, in the erect or 

 sitting posture, the sphere of respiratory movements, as seen and mea- 

 sured, is chiefly limited to the region which is bounded above by a hori- 

 zontal line extending outwards from the lower extremity to the sternum, 

 and below by a similar line extending from the umbilicus to the anterior 

 spine of either ilium. In the recumbent posture, when the abdominal 

 muscles are relaxed, the movement extends lower over the abdomen. Yet 

 the measurements are by no means commensurate with the apparent move- 



