INFLAMMATION OF THE PLEURA. 275 



that, as far as the effusion reaches, the thoracic wall does not take pait 

 in the respiratory movement. This is, in some degree, owing to in- 

 filtration and palsy of the intercostal muscles from collateral fluxion, 

 and partly because the dilatation of the chest is physically impossible 

 when the lung cannot expand. If the diaphragm be so much de- 

 pressed as to form a projection into the abdomen, and if its muscles 

 be not paralyzed, the contraction of the organ, with every inspiratory 

 act, tends to flatten the convexity, which now, of course, is on its lower 

 surface, so that, in these very rare instances, the epigastrium, instead 

 of rising, sinks, during inspiration, upon the side where the effusion is 

 situated. 



If, as absorption of a pleuritic effusion progresses, the compressed 

 lung again undergoes perfect expansion, there generally remains no 

 sign of the disease which has just passed away. When the absorption 

 is complete, the intercostal spaces again form shallow furrows, being 

 once more exposed to the elastic traction of the lung. The dilatation 

 of the thorax is corrected, the derangement of the respiratory move- 

 ments has ceased, and the dislocated heart and liver have returned to 

 their proper situations. Sometimes, however, after perfect absorption 

 of the effusion, the heart, having become fixed by adhesions, remains 

 out of place. If, however, the lung do not expand as the effusion be- 

 comes absorbed, all the dimensions of the chest seem to undergo reduc- 

 tion, and, more especially, its length and antero-posterior diameter, 

 the ribs coming close together, and even overlying one another. The 

 more the thorax loses its rounded form, and the more it becomes flat- 

 tened, so much the more is its capacity diminished, even although its 

 circumference remain the same. Hence, in cases where absorption of 

 the exudation has commenced, if we wish to watch the progress of the 

 reabsorption, and of the restoration of the lung, it is urgently recom- 

 mended not only, from time to time, to measure the two halves of the 

 chest, but to ascertain the length of the two vertebro-mammillary diam- 

 eters by means of the callipers, and to compare the results of the two 

 measurements. A still surer method is to draw accurate ideal sec- 

 tions of the two halves of the thorax, by means of the Kyrtometer of 

 Wbillez, which can be laid one upon the other and accurately compared 

 at leisure. The more the ribs of the affected side are pressed together, 

 so much the lower will the shoulder of that side descend, and so much 

 the greater is the curvature of the spine. The collapse of one half of 

 the chest, the depression of the shoulder, and the lateral curvature of 

 the spinal column, the convexity of which is toward the sound side, 

 are often so great as seriously to deform the patient, who is said to 

 be " grown out of shape." 



Finally, in cases where the lung has not reexpanded after absorp 



