The slice acts as a false bottom for a galley tray, allowing compositors to slide large blocks of tied-up type directly onto the imposing stone without lifting them. By pulling the slice out from under the form, the heavy metal type transfers smoothly and safely. This prevents the composed lines from squabbling or falling apart during the move from the composing frame to the stone.
Heard on the job
Slide the slice out carefully once you have the form positioned on the stone so we don't drop the bottom lines.
Insider tip
Older wooden slices often warped from moisture in the shop, making metal versions the preferred choice for handling heavy book pages.