Answer:
Upon impact,
A lot of people only know that the ship came to a halt. Most people were indifferent.
The wife of Astor went back to bed, Lieutenant Steffanson who had been drinking a Lemonade resumed his pre-occupation.
Some of the card players were too concerned about their game to be concerned. For the most part of the chapter, many people were unaware, others who noticed didn't realise the gravity of the damage and how it would define their lives.
Walter Lord showed the reaction of people to the experience of the impact partly to show that they had the utmost confidence in the vessel and partly because it presents a great contrast to their reaction afterwards when the ship starts to sink.
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