You grind your pill and drop only a little into the test tube. Notice that there is a little of test reagent so you drop only a little of your sample, less than the test reagent. You will have right away orange color in the first vial and dark grey in the second. Then you take your 365 nm UV light and watch the fluorescence it will be orange and dark green for the second vial. Why do we need two test vials, in most cases we can get away with just one test vial but second vials provides confirmation if it is indeed the substance we are looking for. See instruction for color coding.