The intensity of the flow of  bio-energy. In a particular meridian is not the same throughout the day. The flow of bioenergy in a meridian is maximum only once at a definite time during twenty-four hours. Twelve hours after that time the bioenergy flowing in that meridian is the minimum. This has been explained in the following figure which can be termed ‘the organ-clock’ :  The figure 3.3 shows that the lungs have the maximum flow of bioenergy during 3 to 5 ·o’clock in the morning; the kidneys, during 5 to 7 in the evening; the gall bladder, during 11 to 1 at night and the liver’ during 1 to 3 after midnight.   Attacks of asthma mostly occur during 3  to 5 in the morning,  renal colic occurs during  5 to 7 in the evening, the pain in the gall-bladder occurs during 11 to 1 at night and the headache and insomnia which are caused by malfunctioning of the liver occur during 1 to 3 after midnight.  These facts are significant and any doctor will confirm them.