Tally sticks were used by officials of the Exchequer as physical proof of payments to the king, functioning in the same way as a modern receipt. Made of hazel wood, the sticks contained notches denoting the amounts that had been paid; the notched sticks were split into two lengthwise, one half (the stock) being held by the payer and the other (the foil) being retained by the Exchequer. When the accounts were audited, the pieces were fitted together to check that they tallied (hence the name). In the Dialogue of the Exchequer, Richard fitz Nigel (d. 1198) wrote, ‘Let me briefly explain how tallies are made ... The length of a lawful tally is from the tip of the index finger to the tip of the outstretched thumb.’ A pound was represented by a notch the size of a swollen barleycorn, and a penny by a single cut without removing any of the wood.