The Manual of Heraldry; Fifth Edition / Being a Concise Description of the Several Terms Used, and Containing a Dictionary of Every Designation in the Science

by Anonymous

ARGENT signifies silver or white: it is left quite plain.

GULES signifies red: it is expressed by lines drawn from the chief to the base of the shield.

AZURE signifies blue: it is represented by lines drawn from the dexter to the sinister side of the shield, parallel to the chief.

VERT signifies green: it is represented by slanting lines, drawn from the dexter to the sinister side of the shield.