Dubbed L13, the drawing was found in South Africa’s Blombos Cave, a fruitful Middle Stone Age archaeological site that has produced some of the oldest evidence of human cultural activity.

Even young viewers of “Harold and the Purple Crayon” may feel they’ve seen versions of most of these effects before. For what made the book special wasn’t just that Harold could draw anything.

Appraisal: 1933 Barney Nelson Crayon DrawingCascade PBS is your local station. Change ...