Sholes and Glidden typewriter seeking to diversify, Remington further refined the typewriter before finally placing it on the market on July 1, 1874. During its development, the typewriter evolved from a crude curiosity into a practical device, the basic form of which became the industry standard. The machine incorporated elements which became fundamental to typewriter design, including a cylindrical platen and a four-rowed QWERTY keyboard. Several design deficiencies remained, however. The Sholes and Glidden could print only upper-case letters—an issue remedied in its successor, the Remington No. 2—and was a "blind writer", meaning the typist could not see what was being written as it
Particle Transfer Roller Particle Transfer Roller The Particle Transfer Roller, often abbreviated to PTR, is a device for cleaning motion picture film. It consists of a cylindrical roller coated with urethane, over which the surface of the film passes. The Particle Transfer Roller was developed by Eastman Kodak and launched in 1989. It was intended to replace the organic solvents that were the main method of film cleaning before that point. Although their effectiveness is not usually considered sufficient for lab operations, where ultrasonic cleaning with a solvent solution remains the standard, the PTR sold widely for use in projection booths and transfer