This is the original instruction manual for the Endocardiograph. Provides the Acoustic CardioGraph (ACG) owner useful background information for operating the machine. A complete permanent recording can be taken in less than five minutes. The record clearly indicates the amplification and recording of different heart sounds. The Endocardiograph and ACG are precision instruments and will make apparent many points of nutritional deficiencies before they are sufficiently developed to be detected with the stethescope.