John Harris of Kitty Hawk Kites made the first ever hang glider flight from Grandfather Mountain, North Carolina, on July 13th, 1974. (See the Kitty Hawk Kites page.)
The pilot here has his left hand on the base tube and his right hand on the down-tube, a popular method for ground handling and launching at the time. The transition from ground to air, involving physical and sensory coordination unique in aviation*, is one of the most difficult aspects of hang gliding to learn.
* Learning to launch in a paraglider is similarly challenging, but paragliders were an innovation still 15 years away at this time.
The Dave Meuhl images are undated, but the glider, which I think is an Eipper standard Rogallo, dates them as either 1974 or 1975. (See the Eipper-Formanceof Torrance, California related topics menu.)