pattern is said to exhibit infinite growth if it is such that its population is unbounded. That is, for any number N there exists a generation n such that the population in generation n is greater than N. The first known pattern to exhibit infinite growth was the Gosper glider gun. In 1971, Charles Corderman found that a switch engine could be stabilized by a pre-block in a number of different ways to produce either a block-laying switch engine or a glider-producing switch engine, giving several 11-cell patterns with infinite growth. This record for smallest infinitely-growing pattern stood for more than quarter of a century until Paul Callahan found, in November 1997, two 10-cell patterns with infinite growth. Nick Gotts and Paul Callahan have since shown that there is no infinite growth pattern with fewer than 10 cells, so the question of the smallest infinite growth pattern in terms of number of cells has been answered completely.