Thistle tube height when setting up gas generator

[TT0]

For a gas generator like this, I have seen diagrams of the thistle tube in the water, below the other tube or above it, where is it meant to be?

Also, where is the other tube meant to be because I have seen it in multiple positions.

Thanks!

 

[Borek]

Doesn't look to me like a proper gas generator at all, more like a general idea of one. I would prefer the thistle tube with a tap, otherwise the control over the gas generation is very difficult. If you immerse the end of the thistle tube the gas will not escape through it once the liquid delivered through the thistle tube ends, but a lot depends on the thistle tube diameter and the viscosity of the liquid added. Exact levels of the tubes should be such that the pressure is high enough to force the gas out.

Reliable and safe lab gas generator is a https://en.wikipedia.org/wiki/Kipp's_apparatus

 

[TT0]

I see thank you