[note 1] Briggs sold it to the British Museum, and on 21 May 1857 it was exhibited at the Society of Antiquaries of London by Augustus Wollaston Franks (an antiquary who worked at the Antiquities Department of the British Museum), when it was described as "resembling the Scramasax of the Franks, of which examples are very rare in England; and bears a row of runic characters inlaid in gold".

[2] Since then the weapon has usually been called the Thames scramasax; but the term scramasax (from Old Frankish *scrâmasahs) is only attested once, in the History of the Franks by Gregory of Tours, and the meaning of the scrama- element is uncertain,[3] so recent scholarship prefers the term long seax or long sax for this type of weapon.

[6] The technique of inlaying wire to create decorative patterns and inscriptions was widely used on Germanic and Anglo-Saxon seaxes and spear heads from the 9th and 10th centuries,[8] and is also found on Viking swords from about the same period.

[9] On both sides of the seax is a deep median groove running the length of the blade, above which is a long rectangular panel bordered at the top and bottom with inlaid copper strips.

The inscription on the right, separated from the other by a herringbone design in silver and brass, is the male personal name Beagnoþ or Beagnoth ᛒᛠᚷᚾᚩᚦ, which is assumed to be that of the maker or original owner of the blade.

The first nineteen runes are in the correct order, but the next four (20–23: ᛝᛞᛚᛗ) are in a confused sequence which does not match that found in any other source.

The last two runes (27–28: ᚣᛠ) are swapped with regard to their order in the Vienna Codex, but as these are later additions to the original twenty-four letter runic alphabet their order may have been less stable, especially as the last letter ᛠ is very rare in Anglo-Saxon inscriptions (elsewhere it occurs in the name Jɨslheard ᛄᛇᛋᛚᚻᛠᚱᛞ on a stone found in Dover).

Thus, in Stanza 6 of the eddaic poem Sigrdrífumál the valkyrie Sigrdrífa teaches the hero Sigurd how to engrave runes on his sword to provide magical protection: This poem was not committed to writing until the late 13th century (in the Codex Regius), although it may preserve elements from a much earlier date.

This practice is confirmed by a 6th-century sword pommel from Kent, as well as a 6th-century silver scabbard mouth-piece from Chessell Down, Isle of Wight, which both preserve fragmentary runic inscriptions.

Examples of the earlier, twenty-four letter Elder Futhark and sixteen letter Younger Futhark alphabets are relatively common in continental and Scandinavian runic inscriptions, but inscriptions of the historically later Anglo-Saxon futhorc are rare in England, with most examples of the Anglo-Saxon futhorc being known from manuscript sources.

[31] It is unclear what purpose the inscription of the futhorc served, but Page suggests it cannot be simply decorative, but must have had a magical significance.