Microscope slide

Casting around for a last minute blip today I happened to notice that my grandfather's microscope which is in the dresser was showing signs of damp on it. After taking it out to clean it up I thought one of the old slides might make shot for Tiny Tuesday. I used to love being allowed to look at this when I was a child and it is a much treasured family heirloom.
Thanks Freyjad for hosting the challenge.