We use different methods for broadening people's horizons. Here Sir Watkyn demonstrates the use of a reckoning cloth and jettons - a useful technique for calculations using Roman numerals. It is a simple and interesting way of introducing people to the fact that Roman numerals were still commonly used, whilst helping to develop skills of numeracy in younger visitors - and some adults!
Also visible is Sir Watkyn's set of calculating rods and their carved box. These were devised by Napier, and enable complex multiplications of arabic numerals - beginning to become the norm in the 17th century. Children who have problems with maths can soon learn how to multiply by using these rods, as they only need to be able to add up.