My two new books, “A Collector’s Item: Rowena’s After Dark Regency Romance (just released) and “A Pearl Beyond Price: Rowena’s After Traditional Regency Romance (coming soon) feature a safe with a combination lock that plays an important role in the tale of Alaric and Rowena’s romance. Since I’m a bit of geek with regard to historical accuracy, I had to look into the details of lock technology in the early 19th century.
Interestingly, this was a time of transition in lock technology. As steam power, and particularly the fabric mills driven by it, became major factors in industrialization, the machine tool and manufacturing technologies that would really drive industrialization in the second half of the century were emerging. But, they had yet to significantly impact things like locks, although guns were already becoming more and more precise. The earliest combination lock the modern reader might really recognize is said to have been developed in the 1870’s by Joseph Loch for the famous jeweller Tiffany’s.
However, the earliest known combination lock was excavated in a Roman period tomb on the Kerameikos, Athens. Attached to a small box, it featured several dials instead of keyholes. In 1206, the Muslim engineer Al-Jazari documented a combination lock in his book al-Ilm Wal-Amal al-Nafi Fi Sina'at al-Hiyal (The Book of Knowledge of Ingenious Mechanical Devices). Muhammad al-Astrulabi (ca. 1200) also made combination locks, two of which are kept in Copenhagen and Boston museums. The two locks shown here are good examples of the types of locks in use in the Middle East during this period.
Although well known in the Middle East, it took several centuries for the idea of combination locks to reach Central Europe. Such locks involved a variety of mechanisms, such as the ring, and roller locks shown, as well as wheel, puzzle, letter, number or word locks. Italian engineer Giovanni da Fontana was the first European to make a sketch of the Arab lock idea, in 1420. According to author Jon Millington, master locksmith Hans Bullmann (d. 1535) invented the letter lock, and a variant of it was invented by another master locksmith, Hans Ehemann (d. 1551). Both worked in Nuremberg, Germany.
Locks of this general type were also used in England. Fairly recently, a simple combination lock of this type, dated to between 1550 and 1650 was found in the parish of Hatton in Lincolnshire. Made of a bronze alloy of some sort, it uses symbols rather than letters or numbers to identify the wheels. The heavily corroded lock as excavated is shown at left. An X-ray image makes the symbols used on the lock wheels clearer, right. The sketch below shows all of the symbols used by the locksmith, and the design of the tongue of the lock that retracted to open it.
In the next 300 years, not much changed in the original design, and the locks of the 16th and 17th centuries generally used the same kind of hinged shackle lock depicted above. It was the contribution of a French mechanic, Edme Regnier, who died in 1825, that really made this kind of lock interesting. He doubled the number of rings, as shown in the illustration below, making it possible to change the combination. Usually, this type of lock has 2–5 freely adjustable rings or other elements that release the shackle only when all of them are set to a specific position.
Since my “Rowena books” take place in the working life of Regnier, it is probably the kind of lock that Alaric Montfort, the Earl of Brayleigh, would have used to protect the contents of his safe. The modern reader will certainly recognize it as the precursor of many of today’s bicycle and ski locks.
Although the symbols used on the 16th century English lock shown, and its craftsmanship are very attractive, it’s likely that Alaric’s lock would have followed the more modern, and secure design of M. Regnier. However, I enjoy the mysterious feeling of symbols instead of letters or numbers for the lock Brayleigh uses to protect his greatest treasures; so although his lock probably looked like a Regnier design, I gave it the symbols of the 16th century lock found in Lincolnshire.