[TowerTalk] Springs for erecting loops nd dipoles

[KZ4USA]

What is a good antenna that I can feed fron the end.
I have some tall trees far apart and would like to run a a wire between them up 70ft and not have the
weight of feedline in the middle since there would be no support.
What would be a good antenna design to use for this? What type of feed system would I need, tuner, twin line, coax tuner, etc
Jack 
KZ4USA
Bradenton, Florida