Sealing the gaps in Victorian windows.

[SideWinder]

My bedroom has Victorian sash windows and there are gaps where the two parts of the window join creating a draft.

What is the best way to cure this?

Note - the window in question does NOT need to be opened. I open another window which doesn't have the problem quite as bad.

 

[SideWinder]

So post some pictures then OP! Come on you should know by now.

You honestly want to see photos of my DIY sealed windows?