Segment 1. The narrator begins by describing how the eyes work and comparing them to a photography camera. A series of illustrations show the contrasting parts of a camera and the eye - e.g. the camera lens and the cornea perform similar functions, as do the film and the nerve in the eye. Then the voiceover explains the importance of keeping the eyes healthy and noticing if there are any changes in them, over a montage of workers performing detailed work such as sewing, engraving and typing, and playing sports. A series of illustrations show the different illnesses that the eyes are first indicators of, such as diabetes or throat infections. The narrator stresses the importance of regular eye examinations and provides information about the National Eye Service, over images of people having their eyes tested by opticians. There were 350 National Eye Service Centres in England at this time providing low-priced eye examinations. Time start: 00:00:00:00 Time end: 00:04:46:01 Length: 00:04:46:01