The subambient heat capacities of seven La‐Sr‐Cu‐O samples were measured by adiabatic calorimetry over the temperature range 5 to 350 K. The heat capacity of Sr14Cu24O41was derived from that of the mixed phase of nominal composition SrO:CuO=1:2. No anomalous contribution was identified in the heat capacities of SrCuO2, Sr2CuO3, Sr14Cu24O41, LaSrCuO3.5and La2CuO3. A small anomaly associated with the orthorhombic to tetragonal transformation was identified at the vicinity of 300 K in the heat capacity of La1.90Sr0.10CuO3.90. Onset of Meisner effects in the magnetic susceptibilities of La1.90Sr0.10CuO3.90and La1.4Sr0.6CuO3.7were identified at about 32 and 36 K respectively. The onset of superconductivity in these samples is not accompanied by a break in the heat capacity at the critical temperatures. A series of thermal history dependent anomalies were identified in the heat capacity, magnetic susceptibility and electrical conductivity of La1.4Sr0.6CuO3.7between 234 and 290 K. Annealing at 234 K causes the anomalies to shift to higher temperatures. Cooling below the transition temperature restores the anomalies. The anomalies tend to disappear after prolonged annealing at 380 K in air.