Help me ID this

[BrianJW]

Does anyone have any more info on this watch movement?  It's a small women's movement. Measures 21.5mm in diameter. Hour/minutes only. It's not an escapement I've seen in a watch before. The only marks I can find are the AS and 40(?). No name on dial either. Thanks! 

[oldhippy]

That is a cylinder escapement. As you can see it doesn't have pallets. The balance isn't compensated so timekeeping will very according to the weather conditions. The cal will be A S and what ever that number is.

[Nibbler]

Part watch part thermometer. 

[BrianJW]

Thanks oldhippy! I've seen this type of cylinder escapement on text books and such but not in real life. I figured it was an AS but as for caliber number 40 there doesn't seem to be any information in the pink sheets. 

[oldhippy]

Have a look in the bestfit books which I uploaded here ages ago just do a search. Let me know if the links no longer work.

[BrianJW]

It appears to have expired. 

[oldhippy]

Here you are. These are the other links I posted further down the page.

https://www.mediafire.com/file/mz809lm3bms8zk3/bestfit_part1.pdf/file

https://www.mediafire.com/file/eqbhdor949r0ilp/bestfit_part2.pdf/file

You will need this pasword to open each volume. tickandtock