Ophthalmologist is the specialist doctor of ophthalmology, ie completed the regular course of medicine and specialized in the pathologies and treatment of the eyes and their attachments. Although these doctors are able to perform surgeries, diagnoses, medications, and other care, they are considered secondary care providers, some eye-related diseases are so serious that they have to refer patients to primary care providers.
There are many answers you can choose from. The spinning wheel, for example, spun fiber into yarn. This resulted in clothing. The spinning wheel reached Europe in the Middle Ages.
