Across the room from my desk is a large cabinet full of blueprints and sepia prints. Stacks of large prints that represent the original drawings from which the W. M. Keck Observatory was constructed. Floor plans, foundation plans, the structural steel of the telescope itself.
Every now and then Peggi, our librarian, must dig through these stacks of prints to find some detail of construction. When she does the faint smell of ammonia fills the air, after decades there remains a trace of the chemicals used to create these prints by processes long abandoned in these days of CAD and large format inkjet printers.
For me the smell is very nostalgic. Growing up around the civil engineering offices of my father, blueprints and diazotype sepias were part of my world. I vividly remember the print room, with the big machines, the glare of UV light, the stench of ammonia and other chemicals used to create the prints.
Smells are often powerful triggers for memory. For me the smell of these old prints brings back good memories from so long ago.