Letter to William Wetmore Story
p285“I have been much pleased with Mr Clough's which he sent me and with those of two of his friends Burbidge and Arnold”
Fuller, Margaret. The Letters of Margaret Fuller. Edited by Robert N. Hudspeth. Vol. V. Ithaca: Cornell University Press, 1988.
Inferred Hudspeth identified Thomas Burbidge and the work as Ambarvalia, co-authored with Clough and published in 1849.