# Hydrostatics Hydrostatics is fluid at rest — the branch of [[Fluid_dynamics]] where nothing moves and pressure is the only story. Its single governing fact is that pressure increases with depth in proportion to [[Density]] and [[Gravity]], and acts equally in all directions at a point. Everything else, from a manometer to a dam's thrust, follows from that. ## Why the still case still matters Pascal's principle — that pressure applied to a confined fluid transmits undiminished — is the basis of every hydraulic press, brake, and jack, and of the ISO 1219 circuits the [[WT!Advanced_Manufacturing_Center_of_Excellence|manufacturing]] bridge signs. [[Buoyancy]] is hydrostatics applied to an immersed body. Reading a pressure gauge anywhere in a plant is a hydrostatic calculation with a correction for motion, and net positive suction head — the guard against [[Cavitation]] — is hydrostatics setting how high a pump may sit above its source. The still case is the baseline every moving-fluid problem is measured against. **Reads with:** *All Things Flow: Fluid Mechanics for the Natural Sciences (2019)* — [OTL record](https://open.umn.edu/opentextbooks/textbooks/all-things-flow-fluid-mechanics-for-the-natural-sciences) · [download](https://blogs.oregonstate.edu/salty/all-things-flow-fluid-mechanics-for-the-natural-sciences/). Seeded from the Thury Hydrodynamics Apex Spine book shelf. **On the spine:** [[Buoyancy]] · [[Fluid_dynamics]] · [[Cavitation]] · [[WT!Thury_Hydrodynamics_Compendium]]. <!-- COMPENDIUMLINK:BEGIN g19 — generated from _registry/plans/THURY_COMPENDIUM_SECTIONS.md; do not hand-edit inside --> **Part of the [[WT!Thury_Hydrodynamics_Compendium|Thury Hydrodynamics Compendium]]** — main article for section 2, *Fluids at rest*. Related sections: [[Fluid_dynamics]] · [[Hydropower]] · [[Lake_Superior]]. <!-- COMPENDIUMLINK:END --> <!-- THURYSIM:BEGIN g21 — Thury Compendium microsim (framework build, specs/sims/Hydrostatics.json); do not hand-edit inside --> **Microsim — three.js (Wikitube framework):** *Hydrostatics* <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/thury/Hydrostatics.html" data-title="Hydrostatics"></div> *Built from `MICROSIM_GUIDE/specs/sims/Hydrostatics.json`; part of the [[WT!Thury_Hydrodynamics_Compendium|Thury Hydrodynamics Compendium]] set.* <!-- THURYSIM:END --> ## Wikipedia : Wikitube **Strict pair:** [Wikipedia](https://en.wikipedia.org/wiki/Hydrostatics) : [Wikitube](https://en.wikitube.io/wiki/Hydrostatics) ## Previous hub tags Hubs: `Life_Physics`, `Systems`. Portals: [[PORTAL_Thury_Hydrodynamics_Apex_Spine]], [[PORTAL_Physics]]. --- *Apex Spine wave · 2026-09-10 · stub · microsim layer deferred.*