When Plasticine is loaded with a sphere indenter at a series of increasing loads, time being allowed for the indentation virtually to cease, the yield-values increase markedly. Meyer coefficients, while apparently increasing from values of less than 2.0 at small loads, soon reach a constant high value of about 3.5 and, except perhaps after very long times when they may increase still further, remain approximately constant. But in such experiments, stress, strain and time are all varying. When stress is maintained constant, the rate of indentation (i.e. increase in projected area of indent) progressively slows down with time; but the Meyer exponent obtained under these conditions is found to be less than 2.0. Contrary to the views of earlier workers, it is concluded that Plasticine does work-harden considerably in most accepted senses of the term but the definition of "work-hardening" is too vague for a categorical statement to be made. Plasticine also shows a very slow elastic recovery of considerable magnitude.