2. The years of experiments

In 1439 Gutenberg was involved in a legal dispute with the brother of a deceased member of a group of men who had worked with him on three projects. The first project was concerned with a new technique for polishing gemstones. The second aimed at making mirrors for pilgrims to a regularly occurring religious event in Aachen. The mirrors would catch some of the power of relics on show during the pilgrimage, which could be stored up for later use. Unfortunately for Gutenberg and his team, the pilgrimage was abolished in that year, in order to limit the spread of an infectious disease. This may have caused Gutenberg and his partners some financial problems if they had to pay back loans before they could sell their mirrors.

The last project Gutenberg wanted to keep secret. He went to extreme lengths to do so and, tantalisingly, it remains a secret to this day. Several of the words used to describe it were later used to refer to parts of the printing process. However, before printing was common they could perhaps equally be used to describe other processes which involved stamping or impressing something onto or into something else.

Whatever Gutenberg was involved in, it is clear that he was trying to find new ways of making money, using the most up-to-date techniques. He had around him a group of men who worked on inventions.

The last record of Gutenberg's presence in Strasbourg is from 1444, but we do not know for certain that he was back in Mainz until 1448 when records show that he borrowed 150 Rhenish guilder.