I witnessed vac on gravity today

[adk1]

So I was in the woods tightening lats etc. Some of the lats there were in the open areas were full of sap som 50+ yards long or so. I pulled one stubby off my CV that was toward the top of on of my lats and heard a long and very loud vac sound...I couldnt believe it. then, it started spewing sap all over so I stuck it back on.. I had another one like that toward the bottom of one of my lats and that was really throwing the sap out. Unfortunatly, where my mainline is located, is probably the shadiest area at the bottom of the hill and the majority of my saddles never thawed out today.

[PerryW]

if it's spewing out sap, then it's pressure, not vacuum.

I pulled out the top tap a few years ago where the lower part of the lateral was frozen and the sap came out of the tap like a garden hose. I stuck the tap in my mouth to drink the sap and darn near wore a hole through the back of my throat.

[adk1]

yeah, the top tap hadthe noise the lower tap on the lat had the garden hose

[PerryW]

i get it now.

you know there a good natural vacuum when you put you tongue on the spout and it gets sucked into the dropline.