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.
The spinning mule or mule jenny was created in 1779 by Samuel Crompton. It was a combination of Arkwright's water frame and Hargreaves ' spinning jenny. It was so named because it was a hybrid of these two machines.