sorry cannot recall the name of them right nowGas washing bottle? Dreshell (sp?) bottle is the name. Look at the picture, this is what your talking about?
This is the correct lab glassware for gas washing but there are billions opf ways you can ghetto rig these....
Its logical as long as you only use a small vacuum, had a friend who used this then another NaOH wash bottle to remove the HCl that is sucked away with his disto vacuum, it works still but you go through HEAPS of excess HCl as some is sucked away before its used....
Use a small vacuum as you have and your fine... just make sure to use a NaOH (or other strong base) in another wash bottle after this one or your ghetto vacuum will not last very long...
What its for is to pull the HCl through the solution, and once its done what it can the excess is pulled out, this can help stop outlet pipe clogs as the gas is pulled through it pushes away any crystals forming on the gas outlet.
Can sometimes help to stop over-gassing as with the vacuum pulling it through you tend to stop and freeze, filter, regas more, the downside is with the vacuum it does go through more HCl as it does tend to suck some away without reacting... but hey, HCl is cheap and easy.
-AC