Black Disc, Light driven

I was driving down Manor Rd. when I noticed a ball of light traveling to different points aproximately 5 miles apart(seemed to be at 5 different places almost simultaneously). I continued to drive to Saunders Ice Cream at Loch Raven Resevoir, pulled into small lot in front of field at Saunders. Craft appeared then disappeared and reappeared around 6 times at a distance of 200 feet (disc coninued to move to other points around Baltimore) Ball of Light finally landed in field, Light drive powered down to reveal Black disc approx. 60 feet in diameter.  Event witnessed by 5 others age 11-13 on their bikes. I was seventeen at the time. This was not my last up close encounter that summer.