History teaches that the power of musical healing was well known among people of former times.
Primitive peoples used voice and instruments such as drums and rattles to magnify the healing effect of various herbal medicines. These methods have survived to the present day and are still common among natives and minority groups worldwide. Each must of course answer for himself. When undertones are used they are most often continuous, prolonged, and undisturbed. Their magical power is in proportion with the order of tone intervals which gives value to the undertones.