Wrist rocket or sling shot.

[HDHETLAND at paccd.cc.ca.us]

I guess what I considered to be a sling shot is really a wrist
rocket, which I have been using for a number of years.  I use hex
nuts rather than sinkers, because they are cheaper and more readily
available for me.  I put about a three foot section of brightly
colored nylon twine between the nut and the mono-filament line to
improve the visibility when searching for the end.  The size of hex
nut is selected based on the desired weight.

I dispence the mono filament line from a fly rod's reel.  This can be
a one man operation by mounting the reel on only half the rod and
positioning the rod toward the target tree using a simple holding jig.
My highest tree is about 90 feet and I have been able to put a mono
filament line over it.  For best results pick a time of the day with
minimum wind.
Harvey, N6MM  (HDHETLAND at PACCD.CC.CA.US)