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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.
Classic Patents/US X9430
Early Republic & Industrial Dawn (1790–1839)Mechanical Indexing & Fire-Arms

Revolving Gun

US X9430

Indexed revolving cylinder, locking key, and percussion-cap protection

Inventor(s)Samuel Colt
Grant Date1836-02-25
Filing Date1836-01-09
LocationHartford, Connecticut
US X9430 is Samuel Colt's February 25, 1836 specification for a revolving gun. Its text describes a cylinder carried on an arbor, a ratchet and lifter driven by cocking the hammer, a spring-held locking key, separated percussion-cap tubes, and related long-gun lockwork.
USPTO PDF
Engineering Analysis & Physical Principles

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

Colt's specification links a repeating gun's parts into one sequence: cocking frees the cylinder, the lifter advances a ratchet, a spring-held key re-enters a ward to lock the next chamber opposite the barrel, and the trigger releases the hammer onto a percussion cap.
The Core Breakthrough Mechanism

The cited mechanism is a discrete indexing chain, not a claim to a particular chamber count. Hammer pin p first lifts the locking key so its end r leaves a cylinder ward. The lifter arm d then pushes a ratchet tooth s through the shackle, advancing one chamber. Once pin p passes the key's upper end t, spring m forces r into the succeeding ward. The trigger-held connecting rod then releases the hammer to strike the cap on the aligned tube.

Interactive Real-Time Physical Simulation

INITIALIZING THREE.JS WEBGL SIMULATION...
Pawl-Ratchet Angular Discretization & Internal Ballistic Hoop Stress. Cylinder Hoop Stress 100.7 MPa; Cylinder Index Rotation 72.0° deg (72° step); Muzzle Exit Velocity 304 m/s; Cylinder Bolt Lock LOCKED (0.02 mm) detent; Muzzle Energy 240 J E_k
FrankenSim Physics Core/Live Telemetry
Pawl-Ratchet Angular Discretization & Internal Ballistic Hoop Stress
Cylinder Hoop Stress
100.7MPa[M/LT²]
Cylinder Index Rotation
72.0°deg (72° step)[1]
Muzzle Exit Velocity
304m/s[L/T]
Cylinder Bolt Lock
LOCKED (0.02 mm)detent[1]
Muzzle Energy
240 JE_k[1]
Black Powder Combustion Peak Pressure85 MPa
Hammer Cocking Arc Angle45 deg

Detailed Component Architecture

1Arbor, cylinder, and shackle
The arbor carries the revolving cylinder while a shackle mechanically joins the cylinder to its ratchet.

The specification says the arbor is keyed against turning in the shield, while the cylinder turns by the ratchet and shackle. The claim is the shackle's application to connect those two members, not an unstated modern geometry.

19th-C. Term: ArborModern: Cylinder axis or spindle
2Lifter, ratchet, and locking key
Cocking advances one chamber and the spring key locks that chamber at the barrel.

The lifter's arm d acts on a ratchet tooth; the hammer pin p lifts the key before the turn and spring m restores its end r to the next ward. In plain terms, the gun separates unlocking, indexing, and lockup into a causal sequence.

19th-C. Term: Lifter or handModern: Cylinder-indexing pawl
3Cap tubes, partitions, and shield
The rear percussion caps sit on individual tubes with partitions and a shield around them.

Colt expressly says the partitions prevent fire or smoke communicating from one cap to another. His third claim additionally names the shield as protection against moisture and smoke affecting the lockwork.

19th-C. Term: Percussion-capModern: Impact-sensitive primer cap
4Connecting rod and trigger
A rod joins the hammer's cocked catch to the trigger so the trigger can release it.

The rod is pushed forward while cocking and then caught by the trigger. Pulling the trigger draws the rod from the hammer catch; the mainspring drives the hammer forward. Claim 4 names this rod principle directly.

19th-C. Term: Connecting-rodModern: Trigger-to-sear linkage
Interactive Mathematical Physics & Rigorous Mechanics

Governing Equations & Colorized Principles

Dual-coded visual mapping & live SI telemetry

Discrete angular indexing

consumer
Mathematical Governing Law
Δθ=2π/NΔθ = 2π / {\htmlClass{eq-term eq-term-var_0_n eq-term-emerald}{\htmlData{var=var_0_n}{\textcolor{#059669}{N}}}}
Terms:
Plain English DecoderHover or tap any highlighted phrase
In the physical operation of this mechanism, . For a cylinder with N chambers, advancing one ratchet tooth rotates the chamber pattern by one Nth of a revolution. The patent describes that one-chamber advance but does not specify N.
NN
Quantity Count / Rotational Speed / Winding Turns
Discrete component count, shaft rotational speed, or coil turn count
Count [1] / RPM / Turns

Governs quantity count within discrete angular indexing: For a cylinder with N chambers, advancing one ratchet tooth rotates the chamber pattern by one Nth of a revolution. The patent describes that one-chamber advance but does not speci...

Physical Principle & Engineering Insight

For a cylinder with N chambers, advancing one ratchet tooth rotates the chamber pattern by one Nth of a revolution. The patent describes that one-chamber advance but does not specify N.

Moment balance about a pivot

consumer
Mathematical Governing Law
τ=r×Fτ = {\htmlClass{eq-term eq-term-var_0_r eq-term-emerald}{\htmlData{var=var_0_r}{\textcolor{#059669}{r}}}} × {\htmlClass{eq-term eq-term-var_1_f eq-term-sapphire}{\htmlData{var=var_1_f}{\textcolor{#2563eb}{F}}}}
Terms:
Plain English DecoderHover or tap any highlighted phrase
In the physical operation of this mechanism, is determined by the action of . The hammer, key, trigger, and lever work about named fulcrums. A force applied at a distance from a fulcrum creates the turning moment that moves the connected part.
rr
Electrical Resistance / Gas Constant
Opposition to electrical charge flow or thermodynamic gas constant
Ohms (Ω) / J/(mol·K)

Governs electrical resistance within moment balance about a pivot: The hammer, key, trigger, and lever work about named fulcrums. A force applied at a distance from a fulcrum creates the turning moment that moves the connected part....

Physical Principle & Engineering Insight

The hammer, key, trigger, and lever work about named fulcrums. A force applied at a distance from a fulcrum creates the turning moment that moves the connected part.

Interactive Schematic Sheet (Division 1)

The complete pistol view described in the specification.

1.00x
US X9430 · DIVISION 1Rifled Barrel (Bore Axis)5-Chamber Cylinder (Δθ=72°)Pawl & Hammer (US X9430)
Tap any numbered pin3 Curated Callouts
Callout Pin Inspector

Select Any Numbered Pin

Click pins on the schematic or select from the list below to inspect historical specifications.

Why It Still Matters

The document is an early primary source for the linked problems of indexing, lockup, cap isolation, and trigger release in a revolving firearm. Its claims are narrower and more varied than a later shorthand description of a generic revolver mechanism.

Legal Claims Decoder (8 Numbered Claims)

Compare dense legalistic claims directly with decoded plain-English functional specifications.
Claim #1Independent Master Claim
1/8
Verbatim Historical Legal Text
“The application of the caps at the end of the cylinder.”
Plain English Engineering Translation
Claims placing the percussion caps at the cylinder's end.
Key Protected Innovations:
End-mounted percussion caps

The Historical Bottleneck

The specification itself identifies the practical problem: make successive chambered shots while maintaining a locked chamber at the barrel and isolating neighboring percussion caps.

Why Prior Art Failed

  • •The source does not identify a named prior machine or inventor; this record does not infer one from the facsimile.
The Breakthrough Insight
“Colt assigns separate mechanical work to the hammer pin, lifter, ratchet, locking key, springs, and connecting rod, then describes their order during cocking and discharge.”
After the Grant
This record makes no litigation or manufacturing claim without a separately reviewed historical source.
Civilizational Impact
The document preserves an early United States claim set for component-level solutions to repeated percussion-cap firing: cap placement and separation, smoke protection, trigger linkage, cylinder drive and lockup, and the barrel-arbor union.