Vertical Height position oddity

Hey all,

So have a look at the attached screen shot. You can see that my resolution on the right monitor is 1680 x 1050. I create a figure and then modify its position tag. The last value is the height, which I've asked it to be 768. But, look at the figure. It's clearly taller than the screen, which means it ended up being greater than 1050. This is odd... is there something I'm misunderstanding?