We present a multiwavelength study of L 1274, a dark molecular cloud in the
Cep-Cas void. from objective prism spectroscopy we derive a distance of 20
0 +/- 30 pc to the cloud. CO maps reveal a slightly elongated molecular clo
ud with a diameter of about 2 pc. Maps in (CO)-C-12 (1-0), (CO)-C-13 (1-0)
and (CO)-C-12 (2-1) indicate two distinct features: a "main body" and an ad
jacent "ridge". The kinetic temperature of the CO gas is 10-12 K, calculate
d by a non - LTE method. The total gas mass of the main body is estimated f
rom the CO data to be 25-45 M.. We find a large difference between CO-infer
red gas mass and virial mars, a property usually attributed to HLCs. Howeve
r, the derived mean density of H-2 is at least an order of magnitude larger
than typical for HLCs, i.e. similar to ordinary dark cloud cores. We discu
ss the validity of our mass estimates and the possibility of an external di
sturbance, e.g. a passage of a supernova induced shock-front.