Screw Thread Production to Close Limits

Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. Like many other basic discoveries of mechanics, the screw thread remained little more than a principle for centuries. Leonardo da Vinci developed it further and from it evolved the principle of the screw propeller, but as this did not receive any practical application until many hundreds of years later, he was, like many other advanced thinkers, away ahead of his time. Some of the early uses of the screw thread were its application to the instruments Of torture employed by the Inquisition, to baling or compressing devices and to the earliest attempts at printing. A descendant of the latter still exists in the form of the Old style letter - copying press.