Old skiers’ trick: With a buddy, starting at the top of a hill, hold onto each others’ shoulders for balance and each lift your outside ski off the snow. (The two of you together are leaving one pair of tracks.) Ski toward a tree. As you approach it, let go of each other and go around it, one of you to the left and the other to the right. Then grab onto each other again and continue on for long enough that your tracks can’t be seen from the tree. Voila! Charles Addams’ cartoon re-created.