James: The 1856 Pacific disappearance was underreported, to say the very least, particularly in comparison to the Arctic wreck. There is a lot of information available but it is hard to track down, and there is no definitive source to turn to for all of the information. The best single item you can easily find is the March 22 1856 Frank Leslie's Illustrated (which can be found for as little as $20 from time to time) which contains not only the passenger list as provided by the Collins Line, but also a striking colored illustration of the ship at sea. My guess is that so much time elapsed between the sailing of the ship and the final announcement of loss that the impact was somewhat blunted. Also, if you have access to American Heritage back issues, there was a piece on the Collins Line back in the 1950s by the title of The Calamity Line which gives a brief account of the Pacific disappearance.