This is an OD3, also known as a VR150, as you can probably guess it's a 150V voltage reference tube. It's what they used before we had zener diodes.
Slightly different view, notice the nice glow.
Top view.
This is a 27, one of the earliest indirectly heated triodes from the 1930's. If the shape of the glass looks familiar, it's because you might have seen it before as a lightbulb. The glass envelopes for many early tubes were actually made by lightbulb factories.
Another view of the 27.
Close-up view of where all the amplifying action takes place.
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- PeZook