When the Jews were taken to Gleiwitz they were given no food or water for three days. They were then loaded onto trains and transported. They were put into wagons and taken to Buchenwald. Elie tells the reader on page 69,
"Meir Katz stayed in the train. The last day had been the most murderous. A hundred of us had got into the wagon. A dozen of us got out - among them, my father and I."
For quick clarification 12exited the train at Buchenwald.
During the chapter, Eliser kept his father alive by waking him up and keeping him for being thrown from the train like a sack of flower
This was also a very cruel chapter because workmen discover a large form of 'entertainment' which was throwing pieces of bread onto the train and watching the mostly Jewish prisoners fight over it, out of pure hunger and stress.