================================================================================ P9607 J.J. Brunekreef "A transformation tool for pure Prolog programs: the algebraic specification" This technical report contains the complete annotated algebraic specification of `TransLog', a transformation tool for pure Prolog programs. TransLog supports the interactive transformation of (a part of) a program by means of buttons representing transformation steps. As much as possible, pure Prolog semantics are preserved. The choice of pure Prolog semantics induces a number of conditions that have to be satisfied before a particular transformation step is to be applied.