What is "well staircase"

Well \Well\, n. [OE. welle, AS. wella, wylla, from weallan to well up, surge, boil; akin to D. wel a spring or fountain. ????. See Well, v. i.]

1. An issue of water from the earth; a spring; a fountain.

   Begin, then, sisters of the sacred well.
   --Milton.

2. A pit or hole sunk into the earth to such a depth as to reach a supply of water, generally of a cylindrical form, and often walled with stone or bricks to prevent the earth from caving in.

   The woman said unto him, Sir, thou hast nothing to draw with, and the well is deep.
   --John iv. 11.

3. A shaft made in the earth to obtain oil or brine.

4. Fig.: A source of supply; fountain; wellspring. ``This well of mercy.''
   --Chaucer.

   Dan Chaucer, well of English undefiled.
   --Spenser.

   A well of serious thought and pure.
   --Keble.

5. (Naut.)

   1. An inclosure in the middle of a vessel's hold, around the pumps, from the bottom to the lower deck, to preserve the pumps from damage and facilitate their inspection.

   2. A compartment in the middle of the hold of a fishing vessel, made tight at the sides, but having holes perforated in the bottom to let in water for the preservation of fish alive while they are transported to market.

   3. A vertical passage in the stern into which an auxiliary screw propeller may be drawn up out of water.

   4. A depressed space in the after part of the deck; -- often called the cockpit.

6. (Mil.) A hole or excavation in the earth, in mining, from which run branches or galleries.

7. (Arch.) An opening through the floors of a building, as for a staircase or an elevator; a wellhole.

8. (Metal.) The lower part of a furnace, into which the metal falls. Artesian well, Driven well. See under Artesian, and Driven. Pump well. (Naut.) See Well, 5

   1. , above.

      Well boring, the art or process of boring an artesian well.

      Well drain. (a) A drain or vent for water, somewhat like a well or pit, serving to discharge the water of wet land.

   2. A drain conducting to a well or pit. Well room.

      1. A room where a well or spring is situated; especially, one built over a mineral spring.

      2. (Naut.) A depression in the bottom of a boat, into which water may run, and whence it is thrown out with a scoop.

         Well sinker, one who sinks or digs wells.

         Well sinking, the art or process of sinking or digging wells.

         Well staircase (Arch.), a staircase having a wellhole (see Wellhole (b) ), as distinguished from one which occupies the whole of the space left for it in the floor.

         Well sweep. Same as Sweep, n., 12.

         Well water, the water that flows into a well from subterraneous springs; the water drawn from a well.