Here is an animated GIF of the tube filling from the “measuring specific gravity with a U-tube manometer” demonstration. The full video is here.
Don’t try this alone, it really takes two people to do the filling.
Don’t forget to follow @nbkaye on twitter for updates to this blog. If you have a demonstration that you use in class that you would like to share on this blog please email me (firstname.lastname@example.org). I also welcome comments (through the comments section or via email) on improving the demonstrations. If you do not wish to register with twitter or wordpress to get updates then send me an email and I will add you to the list I send update notifications to.