A turned wood monaural stethoscope, 19th Century. Stethoscope invented in 1816 by Laennec but idea introduced to England in translation in 1825. Monaural stethoscopes used until 1860s although the binaural type started to be used in 1855. The stethoscope was the most reliable and informative tool available for diagnosing cardiovascular disease. The use of the stethoscope increased the understanding of how blood moves through the heart in each cardiac cycle, under normal and abnormal conditions. Although more sophisticated diagnostic methods have come into use since then, the stethoscope has never been discarded