data(meuse)
bubble(meuse, max = 2.5, main = "cadmium concentrations (ppm)",
key.entries = c(.5,1,2,4,8,16))
bubble(meuse, "x", "y", "zinc", main = "zinc concentrations (ppm)",
key.entries = 100 * 2^(0:4))Run the code above in your browser using DataLab