When Cinderella's (or Ashiepattle's, according to the brothers Grimm) wicked stepsisters threw her lentils into the ashes of her cooking fire, salvation came in the form of the friendly birds who helped her to sort them. But had she read the report byMakse et al. on page 379 of this issue, she might have come to a differ ent solution to the problem of how one can go about separ ating two different species of intermixed granular materials. The answer maybe as easy as pouring the mixture into a box in the reported experiments, both the stratification and segregation of a mixture of two types of grain is observed to occur spontaneously as the mixture is poured into a narrow box.
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