The formidable-looking iron studded oak door pictured below came from the mansion house of Carnock in Airth, near Stirling. Carnock was built in 1548 by Sir Robert Drummond, modernised in 1827 and demolished in 1941. Fortunately, its entrance door survived and may be viewed in the
Smith Museum, Stirling
The museum label states: 'Constructed in three thicknesses of boarding and reinforced with iron studs. The hinged panel within the door is an unusual feature possibly designed as a loop hole for a small cannon, to repel attackers'.
It is indeed unusual and the writer can only think of one other example - in the Tower of London, inserted in a portcullis by Henry VIII to beef up the defences.
Scottish tower houses were defended by two doors, an outer of wood and an inner of iron known as a yett. The construction of a yett was ingenious for instead of a normal grill the bars were interweaved in such a fashion that it was almost impossible to break them apart.
Not only doors but windows were protected in this fashion. In the building accounts for Holyrood Palace mention is made of its 'great iron door' together with yetts for the King's rooms and windows. James V, the builder, had cause to be wary having been placed 'under protection' in his youth.
It is often stated that this form is unique to Scotland but this is not quite true. It occurs in northern Italy of which the Papal Prison in Rome provides a good example.
The most common method employed to take a tower house was 'to lay a fire at the door' but this was insufficient in itself. Even if the door was destroyed the yett remained but by keeping the fire going it was hoped to smoke the defenders out. Additional resistance could be offered by 'walling up the door' with turf to avoid this unpleasant fate.
Sir Robert Drummond, however, took defence a step further. A small cannon could be thrust through the bars of the yett and the little panel in the outer door opened to allow a discharge 'grape shot' on the attackers - a canny Scot if ever there was one!
* The yett should be behind the door, not in front. And the door opened outwards whereas the yett opened inwards!
Article by Scottish Castles Association member Brian McGarrigle.