1938 whistle tender won't whistle!

Have you tried increasing the voltage? How much voltage are you applying?  Can't really tell how fast it's spinning in the video, but they have to be moving at a pretty good clip to move enough air to whistle.  Is the fan turning the right direction?  Looks like it is but not positive from the video.  

Spiders(or their nests/webs), or dog/cat hair/fur, or tinsel/fir needles... something along those lines... in the whistle chambers.

Thanks guys, I know it should be that easy that's why it's frustrating me for days now.  I had the cylinder open to check the paper (because it wouldn't whistle. the cylinder was clear, paper was good. I added silicone just to make sure it wasn't leaking air. Should whistle, right? You'd think so. I've also reved that transformer up and still no toot. I even made sure the fan was spinning in the right direction (derp).  It's not dammaged as you can see from the picture, the triangled piece is in place and nothing is twisted.  So if it's nothing mecanical, I'll keep poking at it.......hhmmmmm maybe take out the fan and blow some compressed air from the can of compressed air cleaner see if a sharp direct blast from the straw will wake it up.  I'll keep you posted..

It should whistle with a puff of air blown into the intake by mouth alone. If it doesn't, then the chamber is compromised.

Your chamber is leaking air. I can see on stud at the bottom of the whistle is missing, meaning the back plate is not tight. replace the stud, or with a self tapping screw. Seal the edges all the way around.