The Glocken is a ring of 37 bells made by the Whitechapel Bell Foundry. Three more were cast by Mears and Stainbank of the Whitechapel Bell Foundry in 1873. The bells were cast by Thomas Mears in the Whitechapel Bell Foundry. Thomas II Mears of the Whitechapel Bell Foundry cast the tenor bell in 1842. Thomas II Mears of the Whitechapel Bell Foundry cast the tenor bell in 1841. All 13 bells were cast by Mears & Stainbank of Whitechapel Bell Foundry in 1889. After 200 years it is due to return to the Whitechapel Bell Foundry for retuning. The tower and spire contains 13 hemispherical bells cast at the Whitechapel Bell Foundry. Mears and Stainbank of the Whitechapel Bell Foundry cast the fourth bell in 1881. Mears & Stainbank of the Whitechapel Bell Foundry cast the treble bell in 1929. This bell was cast in 1539 by the Schilling bell foundry in Apolda. Alongside the clock is an enormous bronze bell by the Meneely Bell Foundry. The bells were replaced again by Whitechapel Bell Foundry in 2004. During this time Schiller closely observed the sequence of operations in a bell foundry. It was made by the Perner bell foundry in Passau, Germany in 1990.