Alongside buttons and spindle whorls, the ubiquitous lead seal probably features amongst the commoner artefacts found by detectorists searching farmland. Did you know that some of them date from the 15th century?
An illuminating article written by Mick Cuddeford and published in a detecting magazine 25 years ago discusses lead seals and in particular those from bags of guano. There emerged a fascinating story about bird droppings from South America and how their bag seals can be so interesting for the detectorist who wasn’t in the ‘gold stater league’. Research like this into one of the more common finds proves just how much you can learn from the hobby. Here’s an extract:
From pre-historic times, the contents of farm middens had been used as a convenient source of soil enrichment, as well as ‘nightsoil’ spreading which lasted up to the 1900’s century in certain areas.
Some forms of refuse and manure had unproductive side effects on certain crops however, and from medieval times it had been realised that nitrate-rich bird droppings were a valuable source of fertiliser. It was common then for the better-off to keep dove cotes as a source of meat (if you’ve never tried pigeon pie, then you should!) and the droppings were regarded as prime material for spreading on the land.
However, it needs a lot of pigeons to make much impression on the large acreages that developed following the enclosure acts, and this led to the nitrate trade of South America. Off the coast of Peru there are islands that have been the roost of vast colonies of seabirds for centuries. This has created to a build-up of droppings, or guano, many feet thick, and towards the end of the 19th century this was mined as a commercial export for fertiliser. The Searcher Magazine
Anglo-Continental Guano Works Limited, originally Ohlendorff & Co., had been founded in 1873, and remained a German company until the First World War, when it was reconstituted under British control. It was taken over in 1937 by Fisons Ltd. and closed in 1946.
The bulla – a disc with a tunnel from side to side through which a string is passed – became a popular form of seal during the 18th century. It was found to be more versatile than the rivet-type seals hitherto used on cloth, as it could be attached to a wider range of goods, including the bags, bales and sacks in which they were distributed. The method of sealing was to pass the ends of the package’s tightened drawstring through the tunnel in the blank seal. The latter was then die-stamped to impress the design and grip the string. UKDFD
The best examples of bag seals are to be found at Bagseals.org. My friend Stuart Elton has been collecting seals – donated by detectorists – for a number of years now and the best are to be included in a book. Here are a couple of Anglo-Continental seals from his collection. Notice the trade mark of the cornucopia (horn of plenty) in the first example.
The seal below is from James Gibb and Company of London, importers of Peruvian Guano and Nitrate of Soda, Seed Crushers, and was found by StuE near Colchester.