apothecaries’ weight

apothecaries’ weight

A non-SI (International System) measurement system defined by an Act of Parliament, based in 1824 on the troy pound and after 1855 on the avoirdupois pound, formerly used in clinical pharmacology.

Apothecaries’ weight units
• Grain (0.064 g);
• Scruple—20 grains (0.1280 g);
• Dram—3 scruples (0.3840 g);
• Ounce—8 drams (30.720 g);
• Pound: 
  — Troy pound—12 ounces (368.64 g);
  — Avoirdupois pound—16 ounces (454 g).