The Kirk family have been pioneers in optics since Sidney and Percy Kirk opened their first London workshops in 1919.
Until very recently, we had thought that this was the earliest record of the Kirk family in optics until we came across a patent application lodged in the US in 1916 by the young Kirk brothers who would, at that time have been in their mid twenties.
There are also shipping records showing them visiting South America as early as 1912, presumably to buy the Brazilian quartz which, at the time, was the finest raw material for making glass lenses.
The two young brothers married two sisters, Miriam and Sarah, pictured above.
*Thank you to Karyn Stewart Sokol for your help in this research