What was the problems on coffin ships which Irish emigrants used to travel on ?

Thousands of people wanted to emigrate from Ireland because of the so called famine caused by the potato blight. They were poor people who could not afford the fare for a passenger ship and the unscrupulous ship owners cashed in on their plight by offering them passage on cargo ships that were old and unseaworthy. The ships imported, into Europe, timber and cattle from America and Canada and the people were crammed in overcrowded conditions in the hold as 'ballast' for the return journey. There was rarely enough food, in many cases, the water undrinkable and no sanitation facilities on the ships, meaning that the people had to travel in their own filth.

Escaping from famine conditions in Ireland, many of them were weak and unwell before they started their journey and became easy prey to typhus which was rampant on the ships. Many of the ships did not survive the journey because of their age and condition and of those that did, some 20 to 50% of their passengers did not survive, leading to the term 'coffin ships'

You can read an account of a doctor who boarded one of these ships, which was 83 years old, when it arrived in Canada, at the site below

They were over insured Death traps.

http://en.wikipedia.org/wiki/Coffin_ships

Try "historyplace" or "wikipedia" or "google"