So, what exactly is going on here?
Is this some sort of counter-intuitive fluid? Is it some sort of time-lapse or camera or perspective trick?
Judging on the fact that the liquid is getting lighter in color I’d say there was liquid in the glasses before he started.
I’m sure of it.
Watch the 2nd largest glass from beginning to end. He bumps the glass and you can see the liquid move. Plus the liquid is so thick at the beginning it pours out like sugar water.
Yea, that’s why the glasses have such strange patterns, and the white stuff is very heavy so it looks as if it’s pouring through the water.
Thanks guys!
Nope, don’t think so.
Far be it from me to reveal the secret of any magic tricks. But maybe those large glasses aren’t actually quite as large as they may appear.
There are glasses inside the glasses already filled with a clear liquid.
This.
The inner glass contains the water; the person performing the trick pours the liquid down the inside edge of the outer glass so as not to disturb the water in the inner glass, which would give the trick away. You’re not supposed to bump the glass, though. 
I am sure I can see a cylindrical projection inside the glasses. The pattern on the glasses obscures it somewhat, but not completely.
Stop by a “Magic Supply Shop” in most any large city and BUY a set of these magic glasses for your very own experiments and presentations to visitors to your home.
The visitors will be impressed with your magic powers!
It seems like the largest glass is not large enough to hold enough liquid to fill all four of the other glasses like he does at the end, though. Unless I’m just terrible at estimating volume. Which I am.
-FrL-
This is more support for a small glass inside each glass. Pouring down the edge, the small glass doesn’t have to be filled, making the volume of liquid appear even larger.
I can’t view the video at work, but is it the same principle as the “trick pint glasses” that make it look like you’re downing a pint when in fact it’s only a very small volume in a thin “shell” around the glass?
If it was just a trick glass, then he/she wouldn’t be able to refill every previous glass with the liquid in the largest glass. I think it is fairly obvious that the glass is already full with liquid. As others had pointed out, by the time he/she gets to the big glass, it is pretty dilute. A way to fix this would be to use phenolphthalien in each glass, and make the initial glass very basic. That way there would be no dilution effect.
I’m pretty sure this isn’t an example of forced perspective, if that’s what you meant.
It is just a trick glass. When he fills them up at the end, he’s not filling the inner glass, just the space between the inner glass and the outer glass.
If they are normal glasses that are filled with liquid the pouring would look strange.
–FCOD
The classic name for this magic trick is ‘Multum in Parvo’ and some magic dealers still sell the set of special glasses that make the trick possible. If you buy the props, you can do the trick.
It’s not much of a trick when you just demonstrate the basic effect, as in this video. But if you put a nice presentational story together, it can be great fun and very mystifying as well.