The beveled glass lens in the antique barometer was cracked. The tolerances are very tight fitting the glass in the brass bezel. The glass is friction fit . It is not glued in .
A clock shop sent me the front and back bezels from an antique clock. They needed the beveled glass replaced. I used vintage glass. It is very important to use antique glass when restoring a clock. Using new glass will greatly effect the value of an antique clock.
The bezels look round but very rarely are . I have and use old glass from the period the clock was made. The equipment I use to bevel the glass is all so period. Most of my machines I use are as old if not older than the the clocks. The machines are run by leather belts and use lead babit bearings. The beveling and polishing equipment are power by electric motors not steam engines as originally.
Note the small pitts in the glass .
The beveled glass lenses are made to very tight tolerances and are install in the bezel . They are not glued in.
I was told this is from a fire engine . Its is made of flashed red glass and has a beveled edge and a number six engraved on it. Flash glass is made by layering two colored glasses together in this case red and clear. I have restored many carriage lamps over the years I wish I had photographed them now. I also make globes for oil lamp like on the railroad.