  Specific heat measurements down to 0.5 K have been performed on a single
crystal sample of a spin-ladder like compound
Cu$_{2}$(C$_{5}$H$_{12}$N$_{2}$)$_{2}$Cl$_{4}$ under magnetic fields up to 12
T. The temperature dependence of the observed data in a magnetic field below 6
T is well reproduced by numerical results calculated for the S=1/2 two-leg
ladder with $J_{\rm{rung}}$/$J_{\rm{leg}}$=5. In the gapless region above 7 T
($H_{\rm{c1}}$), the agreement between experiment and calculation is good above
about 2 K and a sharp and a round peak were observed below 2 K in a magnetic
field around 10 T, but the numerical data show only a round peak, the magnitude
of which is smaller than that of the observed one. The origin of the sharp peak
and the difference between the experimental and numerical round peak are
discussed.
