"Mughal (1993) proposes the following outline: On the Pakistan side, archaeological evidence now overwhelmingly affirms that the Hakra was a perennial river through all its course in Bahawalpur during the fourth millennium . . . and early third millennium B.C. About the middle of the third millennium B.C., the water supply in the Northeastern portion of the Hakra [the Yamuna] was consider- ably diminished or cut off. But, abundant water in the lower (southwestern) part of this stream was still available, apparently through a channel from the Sutlej. . . . About the end of the second, or not later than the beginning of the first millennium B.C., the entire course of the Hakra seems to have dried up. (4)"