The text on the plaque reads: Here as he walked by on the 16th of October 1843 Sir William Rowan Hamilton in a flash of genius discovered the fundamental formula for quaternion multiplication i² = j² = k² = ijk = −1 & cut it on a stone of this bridge.
Hvilket kan oversættes til "Her, hvor han gik forbi den 16. oktober 1843, opdagede Sir Willian Rowan Hamilton i et glimt af genialitet den fundamentale formel for kvaternionisk multiplikation i² = j² = k² = i j k = −1 & ridsede det i en sten på denne bro."