I think our polypropylene measuring cylinders must shrink with age or autoclaving. The black lines mark the height of the water when this '500 ml' cylinder is filled with 500 grams of water. (Well yes, the temperature is only ~20°C, not 25°C). The markings are off by about 50 ml!
Kurt Gödel's Open World
6 hours ago in The Curious Wavefunction