A perfumer's organ is a special set of shelves that lay out all their perfume essences in "families" similar to ranges of notes on a large organ's keyboard.
Since mine's smaller than the big, legit ones, and I keep most of my easily-destroyed essences in the refrigerator downstairs in the basement, I call mine a "kazoo":
I don't think I posted this here; I had it on my regular LJ formerly.
All the herbals/grasses, citruses, etc. are off the shelves unless being used.
Grey ;)