did he manufacture it or somebody else did?
Elswick Ordnance Company and the Royal Arsenal manufactured it.
Armstrong gun
and manufactured in England beginning in 1855 by the Elswick Ordnance Company and the Royal Arsenal at Woolwich.
what is cragside? A Victorian country house. where is it located? Near the town of Rothbury in Northumberland. how is the house and armstrong connected? It was the home of William Armstrong, 1st Baron Armstrong. what is the architectural style of the house? Tudor revival style. what was armstrong's profession? An engineer and an industrialist. was he supportive of weapons? He was the founder of an armament firm and supported weapons. has he designed any weapon? Yes, the Armstrong gun. where were they used? It was used in the Second Opium War.
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Armstrong gun [SEP] Introduction
An Armstrong gun was a uniquely designed type of rifled breech-loading field and heavy gun designed by Sir William Armstrong and manufactured in England beginning in 1855 by the Elswick Ordnance Company and the Royal Arsenal at Woolwich. Such guns involved a built-up gun construction system of a wrought-iron (later of mild steel) tube surrounded by multiple wrought-iron strengthening coils shrunk over the inner tube to keep it under compression.