nigel
And shepherds we shall be,for Accuracy & Discovery
Nigel I guess if the glass sits there with no lid and the oilin it, I believe it just waits to heat up and wait for conduction to happen.
When you draw on it with no lid there would only up ward pressure and no circulation, within the glass cannister.
The holes would cause and circulation within the glass cannister with oil it in.
If the air is sealed then drawing in the stem with no lid would only cause it to come up( that's what your hearing in wills video) the upward pressure cause its a sealed air path.
Having the holes in the lid would cause air to move through it ( the glass canister) and heat the oil properly producing vapor through conduction and radiation.
Will is just suck the glass can up and down with no air moving across the oil its stagnet.100% pressure up and down, not through or over the oil.
Medical, mark
I really need diagrams to discuss this at this point.
![Smile :) :)](/i/s/smile.gif)
You are right as to the conduction of the glass.
The holes on the top ONLY accommodate ingress because nature (and household pets) abhors a vacuum. You need that delta T from the conduction to alter the internal pressure. And for that you need the cap.
Otherwise, the path of least resistance is PAST the holes, NOT through them.
But, both you and I are frustrated by the lack of experimental test equipment. Until we can remedy this, at best, we can only make assumptions (like for example, gaps for airflow)