what do the white on an altimeter mean ?

[Tex-Twil]

Hi,
this is not directly related to CoD but I wonder what do those white stripes on an altimeter mean:

http://f.cl.ly/items/3Q470Q0K2Y3a301S3b1I/altimeter.png

This is a photo of the one from a F6F-3.

cheers,
Tex

[Loada]

It's used to indicate if the altimeter is reading below 10,000ft MSL. It's supposed to help the pilot when reading the instrument so that you don't accidentally read, say, 16,000ft when it's actually displaying 6,000ft - that mistake could be costly, particularly in IFR conditions!