Certified Ophthalmic Technician (COT). The Certified Ophthalmic Technician is the second core designation level confirming knowledge in 19 specific content areas specifically designed to test the certified ophthalmic assistant or program graduate who intends to advance their career in the eye care field.
The original spinning jenny used eight spindles instead of the one found on the spinning wheel. A single wheel on the spinning jenny controlled eight spindles, which created a weave using eight threads spun from a corresponding set of rovings. Later models had up to one-hundred and twenty spindles.
This decreased the amount of manual labor needed. In 1764, a British carpenter and weaver named James Hargreaves invented an improved Spinning Jenny, a hand-powered multiple spinning machine that was the first machine to improve upon the spinning wheel.his decreased the amount of manual labor needed. In 1764, a British carpenter and weaver named James Hargreaves invented an improved Spinning Jenny, a hand-powered multiple spinning machine that was the first machine to improve upon the spinning wheel.