Lung sounds.

Abstract

Lung soundsIn 1819, on the basis of observations with his newly invented stethoscope, Laennec published L'Auscultation Mediate.'In this masterly thesis he described and classified all the major lung sounds and suggested how they might correlate with lung abnormalities.Within three years the Scottish physician John Forbes translated Laennec's thesis into English' and by the end of the nineteenth century the subjective analysis of lung sounds was well established in that the stethoscope had become the hallmark of the physician.Detailed investigation of sound waveforms was impossible until the development of analogue electronics.In the 1960s Paul Forgacs used simple microphones, amplifiers, oscilloscopes, and tape recorders to obtain the first systematic measurements of respiratory sounds.His