well dude...you wouldnt just use one drop of acetone...you would mix a certain amount into it..so you knew how much salvinorin was in there per milliliter...there are about 15 drops per milliliter...so if there is 5 mg of salvinorin per milliliter you would then have around 300 micrograms per drop...you could change the ratio any way you want...and in that way you could easily figure out a dose...its not that hard to figure out