  We obtained medium-resolution spectra of the bona-fide brown dwarf Cha
H$\alpha$ 1, the five brown dwarf candidates Cha H$\alpha$ 2 to 6, two
additional late M-type brown dwarf candidates, all originally selected by
H$\alpha$ emission, and four previously known T Tauri stars, all located in
Chamaeleon I. The spectral types of our targets range down to M8. We show their
spectra and also list their IJK magnitudes from DENIS. All objects have radial
velocities consistent with kinematic membership to Cha I and show Li 6708\AA
absorption. Our Cha I brown dwarf candidates with lithium are young or
sub-stellar or both. Cha H$\alpha$ 1, 3, 6, and 7 are certainly brown dwarfs:
Either they are as old or older than the Pleiades and should have burned all
their original lithium if they were late M-type stars, or, if they are younger
than the Pleiades, $\le 125$ Myrs, they are sub-stellar because of the young
age and the late spectral types ($\ge$ M7), according to three different sets
of evolutionary tracks and isochrones. To classify Cha H$\alpha$ 2, 4, 5, and 8
as either stellar or sub-stellar, evolutionary tracks of higher reliability are
needed.
