The Salt Tower

The Salt Tower was built by King Henry III around 1240, but the upper floor - part of which is shown in this drawing - is a more modern insertion.

This drawing was made in 1919 while the Office of Works investigated several cracks which had appeared in buildings across the Tower. The National Physical Laboratory was involved in measuring the cracks, which Office of Works architect Frank Baines had connected to dredging of the River Thames undertaken by the Port of London Authority in 1913. Investigations were carried out over several years to determine the cause of the fractures.