If you were to encounter a thigh bone in the street, you'd probably stop to take a look. You'd possibly call the police. On certain parts of the Thames foreshore such a sight is commonplace.
Reader James Whiteacre sent us these shots of a particularly bone-strewn stretch of the river, just west of Swan Lane in the City. The melange includes (what looks like) an animal's femur, assorted rib bones, oyster shells, lumps of coals and the odd clay pipe.
Many of these artefacts will have lain here for decades or even centuries, washed twice a day by the tidal Thames but rarely moving far. The bones are probably the remains of butchered animals, cast into the river long ago. The clay pipes, readily found along the Thames in central London, were an omnipresent feature of London life before the invention of paper cigarettes. The discarded pipes are so common that one Londoner makes jewellery from them.
It's perfectly legal to wander along the foreshore and take home any of this common jumble from the surface, just be careful of the rising tides. However, digging into the detritus or metal detecting requires a licence. Finds of significance, such as worked pottery, jewellery, coins or other crafted items should be reported to the Finds Liaison Officer at the Museum of London. Those interested in pursuing mudlarking as a hobby should check out the Thames and Field Metal Detecting Society, who have what must be the most eccentric web site in London.