He would have pushed a pin into each hammer so that it strikes the string metal to metal, making the harpsichord sound.
To
@Accy cyclist the question, “am I too old at 62 to learn?” Probably not if your goal is just to amuse yourself. Son of a classically trained piano teacher here. You will need regular access to a piano to practice. Most people completely underestimate the amount of time needed to practice to become just moderately proficient. For me, I wasn’t prepared to sacrifice the time required for the practice. My job involved sitting at a desk for hours so then sitting for a couple of hours every day playing endless scales just didn’t seem the healthy thing to do, so I took up outdoor activities instead.
You will need your own piano to get the practice in. An electronic keyboard will not do. Someone has already mentioned that the keys are not weighted like a piano, so the technique in playing is very different. An electronic keyboard is more of an organ than a piano. With an upright piano, the sound will travel to other flats and probably disturb your neighbours. They weigh an absolute ton (pianos not your neighbours!) so it will be difficult to deliver to an upper floor. If the floors are wooden that is another consideration (landlord permission required?). They also need tuning twice a year. An electronic piano with fully weighted and full size keys with a decent range that mimics the traditional piano would be the solution. You can play with headphones so practice can be at any time of the night without disturbing anyone. Talk to your teacher before buying one.