Twenty years ago the authors (Beale and Fleming, 1964) presented a paper on a
similar topic which noted the increasing application of steam turbines to mill drives,
the relatively low cost of these prime movers, and the relatively high cost of the gearing
needed to make their power available at low angular velocity. It also noted 'the whole
question of gear design is so empirical that ordinary design should be carried out to a
recognised specification'. Some new gearing of that period proved a disappointment in service; in these cases there was a failure to establish at the outset formal technical requirements and contractual conditions.