Vienna was an ideal place for the development of Auenbrugger's ideas of confirmation. At this time, it must have been one of the most unhealthy places in Europe as regards pulmonary diseases. The city was surrounded by walls that occupied the ground now taken up by the magnificent Ring Strasse and the inhabitants were packed into extremely narrow quarters, The modern municipal sanitary {64} conscience is lax enough in our own day, but at that time it had not been awakened to the slightest sense of duty toward the citizens. Narrow, wandering streets lined by high buildings that made an attaché of the British Legation of Vienna speak of the houses of the city, scarcely more than fifty years ago, as "well-like," were the universal rule. It must be remembered that the present magnificent Austrian capital, containing, perhaps, the handsomest single street and some of the finest buildings in the world, is entirely a creation of the last half-century. The old city had every cause to be unsanitary. Situated in the valley of the Danube, liable in the spring-time to serious floodings from the capricious, mighty river, which has been brought under control only in recent years at great expense; in an exposed situation, which makes it a veritable temple of the winds during the autumn and winter; it is not surprising that tuberculosis should have been very frequent. Even with all its improvements in recent years, sanitary, hygienic, municipal and domiciliary, Vienna has at the present time one of the highest death rates from tuberculosis in Europe. In Auenbrugger's time there must have been practically unlimited opportunity for the study of pulmonary diseases of all kinds. How well the brilliant young medical observer took advantage of the opportunities thus afforded him can be judged very well from the passages of his book that refer to chronic pulmonary diseases. He divides the chronic diseases of the thorax in which abnormal percussion sounds are heard into two classes. In the first place, he places those in which the thoracic organs are rendered less capable of resisting disease and become actually affected, because of insidious influences, such as hereditary conditions, depressing circumstances, poverty and poor nutrition. Without really calling it tuberculosis, it is evident that in this group pulmonary {65} consumption is included. The second class consists of affections in which the thoracic organs become diseased from definite, easily recognizable causes. Such are disturbances of the general health in pulmonary affections that follow thoracic disease not completely recovered from. By these diseases Auenbrugger evidently intends cases of pneumonia or other affections of the lungs, or trauma and the like, which are followed by tuberculous processes.