The Dragon Manual is a book kept on Dragons. Often called Book of Dragons the other vikings. As of Right now, Fishlegs is the "Log Master!"
Riders of Berk
During Riders of Berk, the teens put in notes on dragons. The also add information to new dragons they ecountered like the whispering death, changewings, scauldrons, smothering smokebreath, and thunder drum.
Defenders of Berk