There are two beads on each rod in the upper deck and five beads each in the bottom one, to represent numbers in a bi-quinary coded decimal-like system.
ðɛɹˌɑːɹ tˈuː bˈiːdz ˌɔn ˈiːtʃ ɹˈɑːd ɪnðɪ ˌʌpɚ dˈɛk ænd fˈaɪv bˈiːdz ˈiːtʃ ɪnðə bˈɑːɾəm wˌʌn, tə ɹˌɛpɹᵻzˈɛnt nˈʌmbɚz ɪn ɐ bˈaɪkwˈɪnɚɹi kˈoʊdᵻd dˈɛsɪməllˈaɪk sˈɪstəm.