The Dial: A Magazine for Literature, Philosophy and Literature was a journal published by the Transcendentalists from 1840-1844. (See this Wikipedia article for more about this publication.) Emerson was the leader of this magazine, and Margaret Fuller was the first editor. Emerson took over the editorship about two years later, after Fuller decided to step aside.
You can view and download what seem to be complete anthologies of The Dial from Google Books. Here are the links:
I have only read selections from The Dial, but am planning to go through these documents; they give the best overview of Transcendentalist thought during the important years of 1840-1844.