An investigation was carried out of the transformation between the number, length, surface and volume size distributions expressed by Johnson＇s S(B) distribution function - the bounded log-normal distribution function. As is well known, if any of the number, length, surface and volume distributions is log-normal, all the others will also be log-normal. Theoretical analysis suggests that the S(B) function may have a similar property. This was confirmed by a computer-aided numerical simulation, in which emphasis was given to the transformation between successive order size distributions, i.e. f(i)(x) --> f(i+1)(x) or f(i)(x) --> f(i-1)(x). The numerical results can be applied to the particle size distribution transformation because this transformation can generally be made step by step, for example, f(i)(x) --> f(i-1)(x) --> f(i-2)(x) --> ... --> f(j)(x) for f(i)(x) --> f(j)(x) (i > j).