Natsu with Lisanna, watching over their Dragon Egg. One day, Natsu found an egg in the forest east of Magnolia. Thinking it to be a Dragon Egg, Natsu took it to the guild and asked Makarov to make it hatch, but Makarov and Erza told him that he was the only one that could make the egg hatch; through love and care.
1 As a Decompression Chamberâ This is a hyperbaric chamber used by surface-supplied divers (commercial divers mostly) to make their decompression stops.  As Recompression chamberâ A hyperbaric chamber is used to treat or prevent patients suffering from decompression sickness.
The left ventricle. The muscle must be much stronger in this chamber because it propels blood out into the systemic circuit. The right ventricle only has to pump blood through the lungs and the atria only have to empty into the ventricles. I hope it helps!