This example demonstrates a force-based cartogram of U.S. county demographics that smoothly transitions into a bubble chart. Built with D3 v4, the visualization uses the same dataset to power a forceSimulation that first distorts county shapes based on population, then morphs each county into a proportional bubble. The transition between the two representations is animated, with SVG rendering. Demographic data for counties is loaded from a CSV file. The code is forked from an earlier block by E. Meek.