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Archaic Legal Glossary & Citations

“Letters Patent”14th–20th Century
19th-C Meaning:

Open public letters from a monarch or government (literae patentes) granting monopoly rights.

Modern Engineering Decoded:Issued USPTO utility or design patent publication.
Historical note: Contrasted with 'letters close' (private sealed royal correspondence).
“In testimony whereof”19th Century
19th-C Meaning:

Formal concluding legal formula affirming under oath the execution of the instrument.

Modern Engineering Decoded:Inventor and witness digital/physical signatures.
Historical note: Required two witness attestations in 19th-century USPTO filing procedure.
“Aeroplane”Early 20th Century (Wright era)
19th-C Meaning:

A flat or cambered lifting aerofoil surface supported dynamically by air pressure.

Modern Engineering Decoded:Wing / Airfoil lifting surface (later evolved to mean the entire motorized aircraft).
Historical note: The Wrights used 'aeroplane' to denote the individual fabric-covered wings.
“Undulating Current”19th Century (Bell era)
19th-C Meaning:

An electric current whose magnitude varies continuously and periodically without interruption.

Modern Engineering Decoded:Continuous analog AC or audio-frequency electrical waveform.
Historical note: Bell's central legal weapon against telegraph companies who relied on pulsed DC make-and-break circuits.
“Subdivision of the Electric Light”1870s–1880s (Edison era)
19th-C Meaning:

The problem of operating numerous small domestic lamps off a single electrical generator.

Modern Engineering Decoded:Parallel circuit wiring of high-resistance incandescent electrical loads.
Historical note: Pundits claimed it was physically impossible until Edison increased filament resistance to 100 ohms.
“Optically Anisotropic Solution”1960s (Kwolek era)
19th-C Meaning:

A liquid solution that exhibits direction-dependent refractive indices due to molecular alignment.

Modern Engineering Decoded:Liquid crystalline nematic phase polymer dope.
Historical note: Technicians initially tried to throw out Kwolek's cloudy solution thinking it was contaminated.
“Unitary Body of Semiconductor Material”1950s–1960s (Noyce era)
19th-C Meaning:

A single continuous crystal structure of silicon or germanium.

Modern Engineering Decoded:Monolithic single-crystal silicon die / integrated circuit wafer.
Historical note: Differentiated Noyce's monolithic planar circuit from Jack Kilby's hybrid flying-wire prototype.
“Peculiar and Novel Construction”19th Century
19th-C Meaning:

A distinctive, patentable structural arrangement not found in prior art.

Modern Engineering Decoded:Novel and non-obvious mechanical embodiment under 35 U.S.C. § 103.
Historical note: Standard 19th-century legal terminology establishing novelty.

Museum Broadside & Archival Print Edition

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The United States Patent & Trademark Archive

Historical Specification & Engineering Broadside

Curated, Verified & Restored by Classic Patents (classic-patents.com)
WATER WHEELA central dividing apex, twin curved bottoms, and flaring discharge sides
US 233,692Class: F03B 1/02 (Impulse water wheels; bucketed runners)
Inventor(s):Lester A. Pelton
Origin / Location:Camptonville, Yuba County, California
Grant & Filing:Filed July 3, 1880 · Granted October 26, 1880

I. Historical Context & Grant Summary

US 233,692 describes a rim-driven water wheel whose bucket divides an incoming jet at a central apex. The two portions travel through distinct curved bottoms and up flaring sides, then discharge at the wheel's sides rather than into the next bucket. The single printed claim also requires a sloped bucket front that lets the stream enter without striking that face.

II. Core Mechanism & Scientific Principles

Pelton's specification starts with a particular nuisance in rim-driven water wheels. A pressurized jet striking a flat or flat-bottomed bucket splashes and reacts against the bucket that follows, slowing the wheel. His bucket uses a central apex to split the stream in two. Each half turns through a separate curved bottom and leaves through an outward-flaring side, clear of the next bucket.

Physical Operation:A nozzle sends water to the wheel's rim. The bucket front b is sloped so an entering bucket does not strike the stream with its face. At the intended position, the jet meets central apex d and divides. Each part runs through one curved bottom c and up an inclined side e. Pelton says that path both receives the stream's momentum and adds the force due to the change in direction. The side exits keep the water from striking the next bucket.
Governing Formulation:
Momentum transfer by deflecting a water stream:F_{\text{tangential}} = \dot{m} (v_{\text{jet}} - u)(1 - \cos\beta)
Avoiding interference between successive buckets:\Delta t_{\text{drain}} < \frac{2\pi}{\omega \cdot N_{\text{buckets}}}, \quad \vec{v}_{\text{exit}} \cdot \hat{n}_{\text{following}} \le 0
Tangential jet application and torque generation:\tau = r_{\text{wheel}} \times F_{\text{tangential}} = r_{\text{wheel}} \cdot \rho A_{\text{jet}} v_{\text{jet}} (v_{\text{jet}} - u)(1 - \cos\beta)

III. The Granted Legal Monopoly (Key Claims)

Claim 1 (Independent)Central dividing apex

The claim protects one complete bucket arrangement: two curved bottoms meeting at central apex d, those bottoms continuing into inclined discharge sides e, and a sloped front b. The front must let the nozzle stream enter the bucket without first hitting the bucket face.

IV. Mechanical Organ Breakdown

Wheel rim and removable or integral bucketsTerm: “hurdy-gurdy wheel” → Rim-driven impulse water wheel

Wheel A has a flat rim face on which buckets B can be attached or formed as part of the wheel.

Dividing apex and twin curved bottomsTerm: “apex” → Central stream-dividing ridge

The jet divides at apex d and each half has its own curved path c.

Flaring discharge sidesTerm: “reactionary force” → Force associated with changing the water stream's direction

Sides e carry the two water portions upward and outward so they leave beside the wheel.

Tangential nozzle placement and sequencingTerm: “distributing-box” → Manifold feeding multiple nozzles

Nozzles F can be placed around the wheel so a bucket drains before receiving water from another nozzle.

CLASSIC PATENTS DIGITAL ARCHIVE • PERMANENT EXHIBIT ID: us-233692-pelton-water-wheel
classic-patents.com/patents/us-233692-pelton-water-wheel
Original USPTO PDF
Classic Patents/US 233,692
Electrification & Early Modern (1870–1920)Fluid Mechanics & Hydraulic Machinery

Pelton's Divided-Bucket Water Wheel

US 233,692

A central dividing apex, twin curved bottoms, and flaring discharge sides

Inventor(s)Lester A. Pelton
Grant DateOctober 26, 1880
Filing DateJuly 3, 1880
LocationCamptonville, Yuba County, California
US 233,692 describes a rim-driven water wheel whose bucket divides an incoming jet at a central apex. The two portions travel through distinct curved bottoms and up flaring sides, then discharge at the wheel's sides rather than into the next bucket. The single printed claim also requires a sloped bucket front that lets the stream enter without striking that face.
USPTO PDF
Audio Engineering Breakdown~2 min listen

Listen to the narrated mechanical breakdown and civilizational context

Engineering Analysis & Physical Principles

How It Works: Step-by-Step Mechanical & Physical Breakdown

Pelton's specification starts with a particular nuisance in rim-driven water wheels. A pressurized jet striking a flat or flat-bottomed bucket splashes and reacts against the bucket that follows, slowing the wheel. His bucket uses a central apex to split the stream in two. Each half turns through a separate curved bottom and leaves through an outward-flaring side, clear of the next bucket.
The Core Breakthrough Mechanism

A nozzle sends water to the wheel's rim. The bucket front b is sloped so an entering bucket does not strike the stream with its face. At the intended position, the jet meets central apex d and divides. Each part runs through one curved bottom c and up an inclined side e. Pelton says that path both receives the stream's momentum and adds the force due to the change in direction. The side exits keep the water from striking the next bucket.

Interactive Real-Time Physical Simulation

Drag to rotate · Pinch to zoom · Shared controls update the displayed model
INITIALIZING THREE.JS WEBGL SIMULATION...
Source-Bounded Divided-Bucket Water Path.
Host-Model Telemetry/Computed Readout
Source-Bounded Divided-Bucket Water Path
Source Water Path
Source
shownreader control[1]
Stream Division
Source
central apex dsource label[1]
Curved Bottoms
Source
two bottoms csource label[1]
Discharge
Source
flaring sides esource label[1]
Source Water-Path Visibility
∂q_{diagram} / ∂u_{reader} (host sensitivity)
1 display fraction / reader-control fraction
Show Source Water Path1 off / on
Claim 1 Geometry1 absent / present
Interval ghosts
Head60.0 m · [10, 150]
Coupled channels
water jet → bucket torque12949 W
Dated scenarios

Detailed Component Architecture

1Wheel rim and removable or integral buckets
Wheel A has a flat rim face on which buckets B can be attached or formed as part of the wheel.

The patent permits buckets to be screwed, soldered, otherwise fastened to the rim, or made integral with the wheel. It supplies no rim diameter, bucket count, material, operating head, or shaft speed.

19th-C. Term: hurdy-gurdy wheelModern: Rim-driven impulse water wheel
2Dividing apex and twin curved bottoms
The jet divides at apex d and each half has its own curved path c.

The single printed claim names curved bottoms c meeting at apex d. That geometry is inseparable from the inclined discharge sides e and the sloped bucket-front b in the claimed combination. The source does not specify a knife-edge radius, exact turning angle, or a percentage energy recovery.

19th-C. Term: apexModern: Central stream-dividing ridge
3Flaring discharge sides
Sides e carry the two water portions upward and outward so they leave beside the wheel.

Pelton says the sides continue the curved bottoms and are inclined outward. The stated functional result is a smooth discharge clear of the next bucket and at the sides of the wheel, avoiding the retarding interaction that opened the specification.

19th-C. Term: reactionary forceModern: Force associated with changing the water stream's direction
4Tangential nozzle placement and sequencing
Nozzles F can be placed around the wheel so a bucket drains before receiving water from another nozzle.

The illustrated distributing-box G feeds two nozzles, though Pelton permits one or more. He says each nozzle can be aimed at the second bucket from the one affected by the prior nozzle. This is a layout option in the specification; it does not appear as an additional printed claim.

19th-C. Term: distributing-boxModern: Manifold feeding multiple nozzles
Engineering Principles & Equations

Governing Equations & Engineering Principles

Authored explanation paired with its stated mathematical relation

Claimed Divided-Bucket Water Path

Source-Bounded Hydraulic ApparatusClaim 1
Mathematical Governing Law
Terms:
Plain English DecoderHover or tap any highlighted phrase
The source-described stream passes the , divides at , follows the two , and leaves through the flaring .
bb
Sloping Bucket Front
Lets the entering stream pass without striking the bucket face before reaching the divided interior.
Source label

The sole printed claim expressly includes the sloping front as part of the protected bucket combination.

Physical Principle & Engineering Insight

This is an authored source-path diagram, not a performance equation. US 233,692 prints no elevation drop, flow rate, wheel speed, cup quantity, discharge angle, efficiency, force, or output wattage.

Historical Context: The card keeps the named geometry of the sole claim visible without importing later Pelton-turbine operating data into the 1880 grant.

Momentum transfer by deflecting a water streamAuthored Principle 1
Stated relationFtangential=m˙(vjet−u)(1−cos⁡β)F_{\text{tangential}} = \dot{m} (v_{\text{jet}} - u)(1 - \cos\beta)
A moving water stream carries momentum. When a bucket changes its direction, the water exerts a force on the bucket in the opposite direction. Pelton explicitly connects the twin curved paths and outward discharge to that additional force, but supplies no numerical deflection angle or force calculation.
Avoiding interference between successive bucketsAuthored Principle 2
Stated relationΔtdrain<2πω⋅Nbuckets,v⃗exit⋅n^following≤0\Delta t_{\text{drain}} < \frac{2\pi}{\omega \cdot N_{\text{buckets}}}, \quad \vec{v}_{\text{exit}} \cdot \hat{n}_{\text{following}} \le 0
The source describes an unwanted feedback path: splash from a flat bucket can react against the next bucket. Splitting the stream and discharging it beside the wheel gives the water a route that does not meet that next bucket. The sloped front also prevents a bucket face from striking the jet before its apex reaches the right position.
Tangential jet application and torque generationAuthored Principle 3
Stated relationτ=rwheel×Ftangential=rwheel⋅ρAjetvjet(vjet−u)(1−cos⁡β)\tau = r_{\text{wheel}} \times F_{\text{tangential}} = r_{\text{wheel}} \cdot \rho A_{\text{jet}} v_{\text{jet}} (v_{\text{jet}} - u)(1 - \cos\beta)
A tangential jet acts at the rim and therefore tends to turn the wheel around its axle. Pelton specifies tangent placement and center strike on the bucket, but does not give a pressure, jet velocity, nozzle diameter, or rotational speed in this patent.

Interactive Schematic Sheet (Fig. 1)

Source Fig. 1: wheel A carrying buckets B around its rim.

1.00x
US 233,692 · FIG. 1bucket B: apex d, bottoms c, sides edistributing-box Gnozzle Fsource arrangement only; no stated head, speed, angle, or efficiency
Tap any numbered pin2 Curated Callouts
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Why It Still Matters

The document makes the classic bucket shape legible as a legal combination. Its central apex, two curved bottoms, flaring exits, and sloped front solve different parts of the same flow problem. The single claim is more specific than the later shorthand “Pelton wheel”: it protects the named geometry that accepts a nozzle stream without letting it hit the bucket face.

Legal Claims Decoder (1 Numbered Claims)

Compare dense legalistic claims directly with decoded plain-English functional specifications.
Claim #1Independent Master Claim
1/1
Verbatim Historical Legal Text
“In a water-wheel, the buckets having the curved bottoms c, meeting at the apex d, and continued to form the inclined discharge sides e, in combination with the bucket-front b, standing at an incline with the wheel-face, so that the stream from the nozzle shall be received into the bucket without striking its face, substantially as herein described.”
Plain English Engineering Translation
The claim protects one complete bucket arrangement: two curved bottoms meeting at central apex d, those bottoms continuing into inclined discharge sides e, and a sloped front b. The front must let the nozzle stream enter the bucket without first hitting the bucket face.
Key Protected Innovations:
Central dividing apexTwin curved bottomsInclined discharge sidesSloped bucket front

The Historical Bottleneck

Pelton identifies a problem in pressurized rim-driven water wheels: a flat or flat-bottomed bucket splashes and reacts against the next bucket, retarding the wheel.

Why Prior Art Failed

  • •Flat and flat-bottomed buckets splashed and reacted against succeeding buckets.
  • •Pointed and other shaped bottoms had been used to address the problem, but only with some success.
  • •A bucket face that strikes the incoming jet can itself retard the wheel before the jet reaches the intended central apex.
The Breakthrough Insight
“Make the bucket a two-part flow path: a central apex divides the jet, curved bottoms receive the two parts, and outward-flaring sides discharge them clear of the next bucket.”
Civilizational Impact
This compact patent preserves the bucket geometry behind a recognizable class of impulse water wheel. It explicitly ties the wheel's turning force to the momentum of the incoming stream and the force produced by redirecting it, while keeping the claim limited to a defined bucket-and-front arrangement.