Found them at a garage sale, New looking, still in box, Mephisto Copying Pencils, thought they were like pencils or charcoal and so used them instead.
But upon playing with some watercolors I discover that they have the curious property of turning purple when when wetted, like watercolors, but the line is that of a standard pencil. So I google it and find this:
Link: https://en.wikipedia.org/wiki/Copying_pencil
Not nearly as new as they appeared, and I'm glad I found out - time to find some tools a little less toxic and more to my purpose.