What kind of whistle sounding instrument is it that for example can be heard throughout this song (first time at 0:47)?
It also serves as the whistle of Mysterious Mose:
I found something called "siren whistle" which shares the characteristic raise and fall of pitch, but looking at a few videos I found the pitch change to be a bit slower, and the timbre not as "pure" but rather a bit more "sawtooth" sounding. Less like a flute/whistle and more like an angry bee if you get what I mean. And it is obviously not a slide whistle. What is it?