This letter relates to materials suitable for making compasses for aeroplanes. Such compasses would have to be reliable, able to survive the rigours of flight and not wear out. The letter is an example of the more unusual subjects that the Geological Survey was consulted about during the First World War.
Posters relating to the Survey's contribution to the war effort 1914-1918 can be viewed here
Malmesbury Abbey, Malmesbury, Wiltshire. Looking north-east. Malmesbury Abbey was constructed in the 12th century of pale yellow, oolitic limestone from the Middle Jurassic limestones of the Bath area (Box Ground Stone). Only part of the Abbey now remains intact. The pale yellow oolitic limestones used in the Abbey have proved to be reasonably durable probably because the building is in a rural setting away from the problems caused by the industrial pollution of the last few centuries. A monastery was established on the site in around 676 but this building dated from the 12th century when the building was consecrated in 1180. The south portch is the most natable feature that survives from that period. At one time the abbey had a spire taller than salisbury Cathedral but it fell down some time before the Reformation when Henry VIII dissolved the monastery in 1539. Dissolution of the monastries in the 16th century lead to the stripping, sale and removal of building materials from many monastic buildings such as Malmesbury Abbey. Date taken: 1977
One of the characteristic features of Norman ecclesiastical architecture is the high quality of the building materials selected and the outstanding workmanship of their masons. The remains of Malmsbury Abbey, now the parish church still preserve examples of this fine craftsmanship in stone. Considered to be one of the most outstanding examples of Norman decorative stone carving in Britain, this doorway in the south porch of the Abbey is carved from oolitic limestone from the Middle Jurassic, Box Ground Quarries near Bath. The limestones generically known as Bath Stones are one of the principal sources of building limestone in the United Kingdom. They were worked from numerous mines in the vicinity of the Bath which now sits upon several kilometres of old stone mine galleries. The limestones are pale to dark yellow in colour and dominantly oolitic though some shelly ragstone beds were also worked. Posted by Bob McIntosh