When the laptop starts presenting Gate Addresses, the 7th symbol is the symbol for earth. as the 7th symbol is always the source, these addresses wouldn't work if dialed from the Aschen Stargate.
Daniel looks at an old newspaper and says it resembles an ancient Celtic text he found in Wales. The Celts and Picts used Ogham for all writing. Most Ogham letters are combos of straight upright and horizontal lines. Think of the hybrid love children of Ts, Fs, and Ls. The paper is clearly in a Gothic form of the Latin alphabet.