It was just this that Laennec did. He solved the riddle of the sounds within the human workshop, to continue the quaint old figure, and pointed out which were the results of health and which of disease. Not only this, but he showed the difference between the sounds produced in health and disease by those different engines, the lungs and the heart. The way in which he was led to devote his attention originally to the subject of auscultation is described by Laennec himself with a simplicity and directness so charmingly characteristic {145} of the man, of his thoroughly Christian modesty, of his solicitude for even the slightest susceptibility of others and of his prompt inventive readiness, that none of his biographers has been able to resist the temptation to quote his own words with regard to the interesting incident, and so we feel that we must give them here. He says: "In 1816 I was consulted by a young person who was laboring under the general symptoms of a diseased heart. In her case percussion and the application of the hand (what modern doctors call palpation) were of little service because of a considerable degree of stoutness. The other method, that namely of listening to the sounds within the chest by the direct application of the ear to the chest wall, being rendered inadmissible by the age and sex of the patient, I happened to recollect a simple and well-known fact in acoustics and fancied it might be turned to some use on the present occasion. The fact I allude to is the great distinctness with which we hear the scratch of a pin at one end of a piece of wood on applying our ear to the other. "Immediately on the occurrence of this idea I rolled a quire of paper into a kind of cylinder and applied one end of it to the region of the heart and the other to my ear. I was not a little surprised and pleased to find that I could thereby perceive the action of the heart in a manner much more clear and distinct than I had ever been able to do by the immediate application of the ear. "From this moment I imagined that the circumstance might furnish means for enabling us to ascertain the character not only of the action of the heart, but of every species of sound produced by the motion of all the thoracic viscera, and consequently for the exploration of the respiration, the voice, the _râles_ and perhaps even the fluctuation of fluid effused in the pleura or pericardium. With this conviction I forthwith {146} commenced at the Necker Hospital a series of observations from which I have been able to deduce a set of new signs of the diseases of the chest. These are for the most part certain, simple and prominent, and calculated perhaps, to render the diagnosis of the diseases of the lungs, heart and pleura as decided and circumstantial as the indications furnished to the surgeons by the finger or sound, in the complaints wherein these are of use."