The first serial slit-lamp photographs of electric cataracts from the earliest lens changes to dense opacities are presented. The lens vacuole formation seen shortly after electrical injury has prognostic significance in indicating future lens changes. Two major patterns of lens vacuole formation are described, each of which leads to a different onset of cataract formation. When an electrical injury occurs especially to the head the pupil should be dilated within a few weeks after injury and the lens examined for the presence of vacuoles.