How Do You Record a Debt When Nobody Can Read? Split the Evidence in Two

A stick of hazel or willow was cut with notches across its width, with the size of the notch indicating the amount, so a broad cut meant a large sum and progressively finer cuts meant smaller ones. The stick was then split down its length through the notches, producing two pieces each carrying half of every mark. The creditor kept the longer piece and the debtor the shorter, and the two could be matched later to confirm the record. Because wood splits along its own grain rather than along a chosen line, the two halves fit each other uniquely and no third piece can be substituted, which makes the object self-authenticating.

The design addresses a set of difficulties that written records did not:

• •Neither party needs to read or write
• •Neither can alter their half without the mismatch being obvious
• •The amount is readable at a glance from the notch sizes
• •The object is durable, cheap and easily carried
• •Possession of a half is itself the evidence, needing no witness
• •A third party can verify by matching the pieces without knowing either party

The English treasury used these objects as its principal accounting record from the twelfth century until 1826, which is a remarkable span. A taxpayer paying money in received the shorter half as a receipt, and the exchequer kept the longer. They also became a form of credit, because the treasury would issue one in advance of tax expected from a particular source, and the holder could sell that claim to somebody else at a discount rather than waiting, which made the objects tradable instruments circulating as a kind of money. Enormous quantities accumulated in storage at Westminster over the centuries, and the system was finally abolished as archaic in the 1820s.

Notched records are far older and far more widespread than the English use of them. Marked bones from the Upper Palaeolithic carry regular sequences of cuts that are usually interpreted as counting something, and one African example over twenty thousand years old is among the oldest candidate mathematical objects known. Split sticks recorded debts across medieval Europe, in China, in Japan and among Alpine herders, who used them to record milk contributions to a shared cheese-making arrangement and continued into the twentieth century. Knotted cords served a comparable purpose in the Andes at far greater sophistication, recording numbers positionally in a system that administered an empire. The recurring principle is that a physical object nobody can quietly alter beats a written record kept by one party.

The disposal of the accumulated sticks produced one of the more absurd disasters in British history. After abolition, the enormous stock stored at Westminster was ordered to be destroyed, and rather than distributing the wood as fuel to the poor, which was suggested, the decision was taken to burn them in the furnaces beneath the House of Lords. The furnaces were overloaded on 16 October 1834, the flues overheated, panelling caught fire, and the resulting blaze destroyed almost the entire medieval Palace of Westminster overnight. The buildings that replaced it, including the famous clock tower, are therefore a direct consequence of disposing of obsolete accounting records carelessly.

Notches cut across a stick that is then split lengthways give each party a half carrying identical marks and fitting only its partner, which records an amount and proves nobody has altered it, without either party needing to read. The English exchequer used them from the twelfth century to 1826, and they circulated as tradable claims on future tax. Burning the accumulated stock destroyed the Palace of Westminster in 1834.