228 DISEASES OF THE PARENCHYMA OF THE LUNG. 



flammation, and amyloid degeneration of the kidney, will be again 

 referred to under their appropriate headings. 



In recent cases, the right heart, whose outflow is always impeded, is 

 found to be hypertrophied and dilated. In protracted cases, in which 

 the volume of the blood is much reduced, the heart is generally flabby, 

 small, and atrophied, A white coating, like curdled milk, is often 

 found upon the tongue and palate, which microscopically consists of 

 vegetable spores and filaments. The cadaver is usually in a state of 

 extreme emaciation ; the skin is thin, remarkably white, and not unfre- 

 quently covered with scales of epidermis (pityriasis tabescentium). 

 The feet are often cedematous, and one or other crural vein is fre- 

 quently stopped up by a thrombus, the correspondipg leg being tume- 

 fied and dropsical. The entire body is bloodless, excepting the right 

 heart, which, when dissolution takes place gradually, contains tolerably 

 large and soft coagula. 



SYMPTOMS AND COURSE. The course of pulmonary consumption 

 varies in type according as its symptoms are dependent upon pneu- 

 monia alone from beginning to end of the disease, or as they become 

 complicated with tuberculosis at a later stage, or are tuberculous from 

 the outset. In most instances these three forms may be distinguished 

 from one another with tolerable precision. 



We shall first make a brief analysis of the various symptoms ob- 

 served in the generality of cases of consumption, with especial refer- 

 ence to the particular morbid process to which each symptom belongs, 

 and shall then endeavor to draw a comprehensive picture of the prog- 

 ress of each of the three main forms of the disease. 



Increased frequence of respiration, hi greater or less degree, occurs 

 in all forms of consumption, and proceeds from a variety of causes. 

 Moderate acceleration of the rate of breathing is not always accom- 

 panied by that distressing sense of shortness of breath requiring con- 

 tinual forced inspiration for its relief, known as dyspnoea. Even pa- 

 tients far gone in the disease often have no dyspnoea at all, excepting 

 when some transient increase of the destructive assimilation going on 

 in the system demands an additional supply of air. While at rest 

 they are fully capable of supplying their blood with oxygen, and oi 

 eliminating the carbonic acid formed in the system, without any 

 fatiguing exertion. On the other hand, the increased respiratory fre- 

 quence may be combined with a severe and persistent dyspnoea, which 

 of course is liable occasionally to still further aggravation, and is one 

 of the most burdensome symptoms of the malady. 



The augmented frequence of the respiration and dyspnoea of phthis- 

 ical patients is due, in part, to a diminution of the breathing surface of 

 the lung, in part to obstruction of the bronchi by the attendant catarrli ; 



