  We present optical spectroscopy of three brown dwarf candidates identified in
the first 1% of the DENIS sky survey. Low resolution spectra from 6430 - 9150A
show these objects to have similar spectra to the brown dwarf candidate GD
165B. High resolution spectroscopy shows that one of the objects -- DENIS-P
J1228.2-1547 -- has a strong 2.3+-0.05A equivalent width absorption line of Li
I 6708A, and is therefore a brown dwarf with mass below 0.065Msol, and age <
1.5 Gyr. DENIS-P J1228.2-1547 can now be considered a proto-type for brown
dwarfs closer to the hydrogen burning limit than Gl 229B.
