This piece of equipment was salvaged from a chemistry laboratory in the 1960's. Does anyone know how and for what it was used? No prizes, just fun.



The major diameter is a little more than 100 mm.

John

 

http://www.bing.com/images/search?q=Glass+Muller&FORM=IRTRRL

 

Hello,

I did a further search based on @Kermit2 answer.

Use the muller on a slab of marble or granite (ideally porphyry) or a thick sheet of glass to grind and disperse pigments and other materials into paint medium. To use the muller on a grinding surface, it must first be prepared by sandblasting or roughing the surface with 100 grit silicon carbide. Both surfaces of the muller and the grinding slab should be retextured periodically after use. To disperse pigments in paint medium, place a small quantity of powdered pigment on the grinding surface and work in oil or water a little at a time with a spatula until a stiff paste is formed. Begin grinding the paste in circular or figure 8 motions until the paste has a smooth consistency. It is not necessary to bear down with your weight on the muller since the idea here is to dispere rather than to grind the pigment.

http://www.naturalpigments.com/glass-muller-medium.html

Bertus

 

Hello,

I did a further search based on @Kermit2 answer.
http://www.naturalpigments.com/glass-muller-medium.html
Bertus

Our glass mullers are handmade by glass craftsmen at a monastery in Russia.

Wow!

 

You guys are all very close. Yes, it was used for grinding and polishing. In the chemistry department, we used it to resurface the NaCl plates used for IR spectroscopy windows. IR studies at low temp (i.e., many of mine used liquid nitrogen cooling) always faced a problem with water condensation on the salt crystal windows.

While it is often used to grind against a flat when making pigments, for surfacing a window, we held the stem and rotated/ground the NaCl crystal on top.

Next question will be harder. I have used Google image search a few times. I am amazed at how well it works.

John

 

I used a muller similar to that! Can't remember why.
My first gut reaction was that it was related to microscopy or spectroscopy and the salt crystal sounds right somehow. Too many years ago.
Now my only use for mullers is cooking and cocktails.