Merrimack was launched by the Boston Navy Yard 15 June 1855 ; sponsored by Miss Mary E. Simmons ; .
Merrimack was commissioned 20 February 1856 , Captain Garrett J. Pendergrast in command .
Merrimack was launched by the Boston Navy Yard 15 June 1855 ; sponsored by Miss Mary E. Simmons ; and commissioned 20 February 1856 , Captain Garrett J. Pendergrast in command .