> May I suggest that your focus on air flow is incorrect?

Look instead at air volume.  Isn't the pack of biscuits 
basically trying to
hydrate the surrounding air space?  How many ml2 airspace do 
you suppose
there is in total within the confines of the cling film? 
Compare that with
how many l2 of air space there is within the cupboard.  ...

"Brownian motion"  [Gargoyle knows] aka diffusion will allow 
the transportation of molecules at substantial velocity 
through air etc in surprisingly short times. A dissimilar 
gas mix will attempt to establish an equilibrium based on 
the partial pressures of the gases involved.

Useful / interesting experiment: Acquaint yourself (if not 
already acquainted with the smell of "Methylated Spirits" 
that has been denatures with Pyridine. Partially fill a 
container with said spirits and cap securely with a quick 
release cap. (Cork good - screw cap OK). Have an assistant 
(optionally beautiful) stand at the far side of a largish 
[draft | draught]less room with minimal odo[u]rs present. 
Have said assistant shake the capped bottle well to get the 
internal sides wet and air inside well saturated then uncap 
the spirits and note how long it is before you note the 
characteristic smell. You are liable to be very very very 
surprised at the result.


        Russell

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist