They are also called lolly columns.

"Ivan Vegvary" wrote in message
news:yRXvg.10576$Ss2.5238@trnddc01...
Sorry about the cross-posting.

I used to own what I call 'support posts'. 30 years ago I
bought them at
Sears. They are telescoping 3"± tubes with an acme jack
screw on top. Used
for either temporary or permanent support of sagging
floors etc. Mine would
telescope from about 5 feet to 8 feet ±. Need to buy some
since I am
digging a basement under my house. Can't for the life of
me remember what
they are called, and therefore can not find any on the web
or elsewhere.
I've searched under 'jack post', 'house jack', 'support
post' etc.

All help appreciated.

Ivan Vegvary