In the predawn darkness, a procession of druid priests in white robes carry banners by the monoliths of Stonehenge, the ancient British archaeological site. There is an aroma of burning sage; a bagpipe calls in the distance. As dawn approaches, fever-pitched drumming mounts. If you hadn’t already felt the power in the stones at this summer solstice celebration, there is no denying the physical vibration as the sun rises in alignment with the stone circle.