AVE6324566: Scientist Pours Liquid into Glass Beaker in Lab / Bridgeman Images

AVE6324575: Warning Label on Bottle of Pesticide / Bridgeman Images

AVE6324576: Man in Yard Works with Pesticides / Bridgeman Images

AVE6324586: Men Collect Medicines from Pharmacy / Bridgeman Images

AVE6324589: 1910s: Young girl gazes out of window at other girls playing outside / Bridgeman Images

AVE6324596: 1910s: Girl sits in cramped space playing with a doll / Bridgeman Images

AVE6324597: 1910s: Girl sits in cramped space playing with a doll and accidentally breaks it / Bridgeman Images

AVE6324650: United States, 1930s: Pointer showing the layout and structure of the middle ear as seen through an otoscope / Bridgeman Images

AVE6324657: United States, 1930s: Diagram showing the transmission sound from the inner ear to the brain via the frontal, ethmoid, and maxillary sinuses / Bridgeman Images

AVE6324659: United States, 1930s: Close up diagram showing the external ear, shell (pinna), and auditory canal (meatus) / Bridgeman Images

AVE6324668: 1910s: Couple speaks in a kitchen, elderly man walks past outside / Bridgeman Images

AVE6324671: 1910s: Man and woman speak heatedly to each other, young woman talks to herself outside and eventually shoots a gun / Bridgeman Images

AVE6324672: United States, 1930s: Picture showing the inner ear structure / Bridgeman Images

AVE6324678: 1910s: Young woman enters a parlor and overhears people outside concerned that they heard a gunshot, she looks guilty/worried / Bridgeman Images

AVE6324679: United States, 1930s: Close up view of the cochlear on a diagram / Bridgeman Images

AVE6324683: 1910s: Young woman sneaks into a house and looks shocked by what she sees / Bridgeman Images

AVE6324693: 1910s: Man shows woman some papers and then they talk excitedly / Bridgeman Images

AVE6324696: 1910s: Young couple has a disagreement / Bridgeman Images

AVE6324699: 1910s: Young woman hurries out of room, two men on stairs outside notice a spot of blood on the stairs / Bridgeman Images

AVE6324710: 1910s: Man kisses woman on the neck, she doesn’t look happy about it / Bridgeman Images

AVE6325340: 1940s: Map of North America / Bridgeman Images

AVE6325341: 1940s: Map of world / Bridgeman Images

AVE6325350: 1940s: Family picks up Menorahs from dirt and talk to one another / Bridgeman Images

AVE6325351: 1940s: Map of continents and Pacific Ocean / Bridgeman Images

AVE6325352: 1940s: Dates appear over map of continents and Atlantic Ocean / Bridgeman Images

AVE6325356: 1940s: Colored regions appear over map of United States / Bridgeman Images

AVE6325361: 1940s: Clothes hang from lines outside tenement building / Bridgeman Images

AVE6325369: 1940s: People enter government building / Bridgeman Images

AVE6320770: 1970s: Flashing lights on model of brain / Bridgeman Images

AVE6320788: 1970s: Man looks into microscope and adjusts specimen / Bridgeman Images

AVE6320789: 1970s: Specimen in water-filled container with probes / Bridgeman Images

AVE6320792: 1970s: Liquid bubbling on piece of equipment / Bridgeman Images

AVE6320800: 1970s: Hands hold images of brain / Bridgeman Images

AVE6320803: 1970s: Man holds and gestures at image / Bridgeman Images

AVE6320806: 1970s: Baby's hand / Bridgeman Images

AVE6320807: 1970s: Infant lies on stomach / Bridgeman Images