in 1886 the use of lens coatings was not widely known. With war looming the firm began to work with Arthur Pollen on his 'Aim Correction' system for improving the accuracy of naval gunnery. Cooke & Sons supplied the optical components for the system which consisted of a gyroscopically stabilised rangefinder where successive readings of a moving target were mechanically integrated to give a prediction of range and bearing. In the event the British Admiralty for the most part chose the simpler and cheaper Dreyer predictor. In 1914, a new factory was built in Bishophill. In 1915 Vickers acquired a controlling stake in the company. During World War I about half of the factory's capacity was turned over to contracts for large naval rangefinders from the main contractor, Barr & Stroud In 1922 Vickers merged it with Troughton & Simms to form Cooke, Troughton & Simms. See also Cooke Optics Grubb Parsons - contemporary Irish telescope company, founded in 1833 References Instruments from T. Cooke & Sons at the Hellenic Archive of Scientific Instruments The company archives are held at the University of York Manufacturing companies of the United Kingdom 1837 establishments in England Companies based in York