the.com/caisson
A watertight box that lets humans build foundations where they have no business breathing.
means A large watertight chamber used to keep water and earth out so workers can excavate and build foundations underwater or below the water table — and also, separately, a wheeled chest for carrying ammunition.
from From French 'caisson,' meaning a large box or chest, itself an enlargement of 'caisse' (box, case), which descends from Latin 'capsa' — the same source that gives us 'case' and 'capsule.' The word was first a military term for an ammunition wagon before engineers borrowed it for the sunken boxes that let them dig beneath rivers; the painful 'caisson disease' (the bends) was named for the pressurized chambers in which those workers labored.
- sunk underwater
- Sealed chambers pumped full of air for digging riverbeds
- the bends
- Pressurized workers got crippled surfacing too fast
- brooklyn bridge
- Its caissons cost workers paralysis and lives
- military meaning
- Also a wheeled chest for hauling ammunition
- pressure deep
- Workers labored under several atmospheres of compressed air
brooklyn bridge caisson — used during 1869-1871 construction; workers suffered decompression sickness from rapid depressurization
eads bridge caisson — st. louis, 1869-1874; deepest caisson work of its era at 110 feet below water
mulberry harbour caisson — d-day normandy 1944; massive concrete caissons towed across english channel as artificial breakwaters