a drachm — 3.9 grams, or .14 ounces. This was Ludlow’s highest dose of cannabis extract. Oriana Josseau Kalant, in an article for the International Journal of the Addictions in 1971 estimated that that this extract “was roughly twice as potent as the crude resin and ten times as potent as marijuana” which would make a dose of a drachm equivalent to smoking a quarter-ounce of hashish or nearly an ounce and a half of marijuana at one sitting.