Generally, a disease like this is caused by an infectious agent and not spread between people. Neurosyphilis -- tabes dorsalis, although infectious, is not a genetic disease. It is not caused by a defective or abnormal gene.
1 Movies and animated cartoons. 2  While some color film processes (including hand coloring) were experimented with and in limited use from the earliest days of the motion picture, the switch from most films being in black-and-white to most being in color was gradual, taking place from the 1930s to the 1960s.
In black-and-white photographic film there is usually one layer of silver salts. When the exposed grains are developed, the silver salts are converted to metallic silver, which blocks light and appears as the black part of the film negative.t is removed from the film during the process of fixing the image on the film with a dilute acidic solution such as acetic acid. Fixing leaves behind only the formed color dyes, which combine to make up the colored visible image.