170 years ago today - Aug 20, 1841

Erastus Snow: Left for Salem 20 August 1841.

[Source: Cook, Lyndon W., The Revelations of the Prophet Joseph Smith: A Historical and Biographical Commentary of the Doctrine and Covenants, Seventy's Mission Bookstore, Provo UT, 1985, http://amzn.to/RevelationsofJosephSmith]