A printing press with movable type works by transferring ink from individually set and arranged letters (the movable type) onto paper to create a printed page. Here's a breakdown of the process:
1. Type Composition:
- A compositor selects individual pieces of movable type, each representing a letter, number, punctuation mark, or space.
- These pieces of type are arranged in a composing stick to form words and lines of text.
- The lines of type are then transferred to a galley, a tray used to hold multiple lines.
- Finally, the galley of type is arranged into pages and secured in a chase, a frame that locks the type in place. This ensures the type doesn't move during the printing process.
2. Inking the Type:
- The locked chase, now containing the page layout, is placed on the printing press.
- The type surface is inked. Early presses used ink balls, made of leather stuffed with wool, to dab ink onto the type. Later presses employed rollers to apply the ink more evenly. The ink was typically oil-based.
3. Impression (Printing):
- A sheet of paper is carefully placed onto a tympan, a frame that holds the paper in place.
- The tympan is then folded down onto the inked type.
- Pressure is applied, either by a screw press (early designs) or a platen (later designs), to press the paper against the inked type. This transfers the ink from the type to the paper, creating an impression.
- The paper is then removed, and the process is repeated for the next page.
Simplified Steps in Table Format:
| Step | Description |
|---|---|
| 1. Composition | Arrange movable type into words, lines, and pages within a chase. |
| 2. Inking | Apply ink evenly to the raised surface of the type. |
| 3. Impression | Press paper against the inked type to transfer the ink and create the printed image. |
Key Components:
- Movable Type: Individual pieces of metal (typically lead alloy) with a raised character on one end.
- Composing Stick: A tool used to hold and align lines of type as they are being set.
- Galley: A tray used to hold assembled lines of type.
- Chase: A frame that locks the type in place for printing.
- Ink: A thick, viscous substance used to transfer the image to the paper.
- Tympan: A frame that holds the paper and guides it onto the type.
- Frisket: A paper frame used to mask areas of the tympan to prevent smudging
- Press (Screw/Platen): The mechanism used to apply pressure to create the impression.
The invention of the printing press with movable type revolutionized communication by enabling the mass production of books and other printed materials.
