Variations IV is intended for any number of players producing any sounds by any means, “with or without other activities.” The score consists of seven points and two circles on a transparent sheet. The sheet is cut into nine small sheets. One of the circles is then placed anywhere on a map of the area where the performance is to take place. Then the rest of the sheets are dropped anywhere on the same map and straight lines are drawn from the first circle to the seven points; if a line intersects or is tangent to another circle, the same procedure is applied to that circle. Performers do not need to confine themselves to a performance of the piece during the entire performance and are free to engage in any other activities at any time. The duration of Welcome Inn Time Machine is derived from the 1963 six hour-long premiere performance of Variations IV at UCLA.