The siphon thing has also perplexed me at times. I totally understand the tube / pipe scenario, but as I am sure some of you are aware, the same phenomena can occur using a piece of cloth, or fabric, which soaks up the liquid. I chose to demonstrate this phenomena to a friend by having one glass filled with water on a couple of books, with another glass of equal size next to it, with a long sock acting as the siphon. Now I expected that the majority of the water would end up in the lower glass, but would leave a small amount in the original, higher glass, whilst leaving the end of the sock rather moist- theory being that once the 'siphon' effect has ceased, the remaining water in the half of the sock in the original glass, would fall back into.. the original glass. I wish I could draw a diagram but I have no such ability.
Anyway in the morning, like 4 hours later, the original glass was bone dry, as was the end of the sock that was in the original glass! Even more surprisingly the weight of the water had not pulled out the dry end of the sock, and the entire glass-sock-glass setup had not changed at all. Only the water had completely transferred into the lower glass.. Note it was not a particularly warm, or dry day, so evaporation factor would have been negligible. I fail to see how ALL the water left the original glass. As using a hose, once the water runs out,i.e. the gravity, pressure, vacuum effect ceases, the rest of the water in the tube will fall back into the original container. Does this make any sense??