Development.
The modern cinematograph was rendered possible by the invention in 1890 of the celluloid roll film, on which serial pictures are impressed by instantaneous photography; a long sensitised film being moved across the focal plane of a camera and exposed intermittently. For an hour’s exhibition 50,000 to 165,000 pictures are needed. To regulate the feed in the lantern a hole is punched in the film for each picture. These holes are extremely accurate in position, and when they wear, the feed becomes irregular, and the picture “dances” in an unpleasant manner—hence that irritating feeling which arises from seeing a well-worn film vibrating. The machines have been devised in enormous numbers under the names of bioscope, biograph, kinetscope, mutograph and cinematograph, derived chiefly from Greek and Latin words for life, movement, change, etc.
The first actual attempt recorded seems to be that of a Frenchman named Louis Du Hauron, who took out two patents in 1864. Although they covered all the essential points of the modern cinematograph, the one factor which made it a failure was the slowness of the wet collodion plates of that time as compared with the gelatino-bromide. In 1906, Mr. C. Rider Noble brought out a patent whereby the moving film could be stopped at any moment for examination. Prior to this invention, the film had to speed on to the end without interruption.
New ideas and inventions seem to add improvement daily.