  We have performed a series of elastic neutron scattering measurements on
1/8-hole doped La$_{1.875}$Ba$_{0.125-x}$Sr$_{x}$CuO$_{4}$ single crystals with
{\it x} = 0.05, 0.06, 0.075 and 0.085. % Both charge-density-wave (CDW) and
spin-density-wave (SDW) orders are found to develop simultaneously below the
structural transition temperature between the low-temperature orthorhombic
(LTO) and low-temperature tetragonal (LTT) or low-temperature less-orthorhombic
(LTLO) phases. % In the ground state the CDW order is observed only in the
LTT/LTLO phase and drastically degrades towards the LTO boundary. The {\it
x}-dependence of {\it T}$_{c}$ strongly suggests a direct effect of the CDW
order on the suppression of superconductivity. % Results are discussed in
comparison with those from the La$_{1.6-x}$Nd$_{0.4}$Sr$_{x}$CuO$_{4}$ system
within the framework of the stripe model.
