distinct offenses

possessing and selling are distinct offenses. One may obviously possess without selling, and one may sell and cause to be delivered a thing of which he has never had possession, or one may have possession and later sell. The fact that the person sells the liquor which he possessed does not render the possession and the sale necessarily a single offense. There is nothing in the Constitution which prevents Congress from punishing separately each step leading to the consummation of a transaction which it has power to prohibit and punishing also the completed transaction.