Another "what is it" item

[Jon Shiu]

This item stands about 5-6 inches tall. When you look in the eyepiece, there is a fine sawtooth indicator that moves when you turn the knob.

I have no idea what it is. Bought at estate sale, because why not?

 

[MattKing]

I think I saw one of those on Robert DeNiro's belt in "Brazil"

Something used by a surveyor?

 

[Jon Shiu]

Thanks, I also see some very fine "wires" running vertically in the viewfinder.

 

[BAC1967]

Looks like a micrometer for a microscope.

https://microscope-antiques.com/gvhmicroeye.html

 

[BAC1967]

This is one I use made by Bausch & Lomb. Yours looks older.

 

[Jon Shiu]

Thanks, for measuring very small.

 

[AgX]

But what is that bar at its tube for?
I have not seen microscopes with slotted tubes. Morover, fixing the rotational angle of a such scale makes no sense.

May it be a distance arrest, for some short-tube microscope?

 

[snusmumriken]

@BAC1967 has the answer. As to how it works ... does the distance between the wires change when you turn the knob? In which case, you can quickly measure the length of an object (or rather, of its image) in a microscope or other optical device. Slotted tubes are usually to prevent the eyepiece falling out too easily.

 

[BAC1967]

@BAC1967 has the answer. As to how it works ... does the distance between the wires change when you turn the knob? In which case, you can quickly measure the length of an object (or rather, of its image) in a microscope or other optical device. Slotted tubes are usually to prevent the eyepiece falling out too easily.

Turning the knob moves a marker against the scale so you can get a precise measurement. The scale will change depending on magnification so you need to calibrate the scale to a known measurement. I have a micrometer scale that I put on the stage for calibration. I don't know of a microscope that had a slotted tube but there were a lot of different makers back when that one was produced, like AgX said, it could just be a stop.

The one thing it has that mine doesn't is the two adjusting knobs either side of the eye piece. Looks like they may be for fine tuning the focus but usually eyepieces are fixed.

I'm sure someone on the MicrobeHunter.com Microscopy Forum would know more about it. If Jon wants, I could share his photo on that forum and find out more about it.

 

[AgX]

Bought at estate sale, because why not?

I know this. But there may come the day when one still got no clue what to do with such.
In your case it still may be an item for ones cabinet at least.


Concerning those two screws, to me they are just to fix that stage to the tube.
Why they are made as thumpscrews? Maybe for exchanging stages.