Flask is a British unit of mass or weight in the avoirdupois system, used to measure mercury.[1][2][3][4][5] It is defined as 76 pounds (34 kg).[1] Near room temperature, a flask of mercury occupies a volume of approximately 2.5451 litres (86.060 US fl oz; 89.575 imp fl oz).[6]
^ abcCardarelli, F. (2003). Encyclopaedia of Scientific Units, Weights and Measures. Their SI Equivalences and Origins. London: Springer. p. 37. ISBN978-1-4471-1122-1.