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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

Authentic archival layout formatted for framing, study, and high-resolution printing

Paper:
Theme:
The United States Patent & Trademark Archive

Historical Specification & Engineering Broadside

Curated, Verified & Restored by Classic Patents (classic-patents.com)
IMPROVEMENT IN MAGNETO-ELECTRIC MACHINESClosed Series of Small Coils, Contact Rubbers, and Continuous or Alternate Induction Currents
US 120,057Class: H02K 23/04 (permanent-magnet-excited DC commutator motors or generators; current catalog classification)
Inventor(s):Zénobe Théophile Gramme, Eardley Louis Charles d’Ivernois
Origin / Location:Paris, Empire of France
Grant & Filing:Filed August 17, 1870 · Granted October 17, 1871

I. Historical Context & Grant Summary

US 120,057 describes several magneto-electric machines built around a continuous series of small coils on a soft-iron ring, cylinder, disk, or moving chain. Contacts at selected coil junctions collect currents that the inventors describe as continuous or, in a stated alternate-current arrangement, opposite in direction. The grant issued October 17, 1871 after a United States application filed August 17, 1870.

II. Core Mechanism & Scientific Principles

The source’s problem is how to take induction from many small coils as a rotating magnetic relation changes, while avoiding a visibly interrupted output. Gramme and d’Ivernois connect the coil sections into an endless circuit, put an accessible conductor at each junction, and use contacts placed between unlike poles to take the like-directed currents that meet there. The patent also sets out a different connection for alternate current; it is not confined to a single later textbook form of the Gramme dynamo.

Physical Operation:Let a coil section move through magnetic flux. Its induced electromotive force follows Faraday’s relation $\mathcal{E}=-N\,d\Phi/dt$. Around the closed series, sections before unlike poles induce currents whose directions bring like current together at selected junctions. The metal rubbers contact those junction conductors as they pass and take the combined current. The polarity depends on rotor direction, coil handedness, and the north-to-south order, conditions the specification expressly states. In the alternate-current version, two perpendicular pairs of diametrically opposite junctions are connected through the shaft and isolated rod.
Governing Formulation:
Faraday’s law of electromagnetic induction:\mathcal{E} = -N\,d\Phi/dt
Series connection and selected current collection:V_{\mathrm{series}} = \sum_i \mathcal{E}_i
Magnetic-circuit reluctance:\Phi = \mathcal{F}/\mathcal{R}

III. The Granted Legal Monopoly (Key Claims)

Claim 1 (Independent)Endless series of small bobbins

Claim 1 covers the stated endless closed series of small coils or conductive strips/ribbons on a magnetic core, positioned relative to fixed or moving permanent or electromagnet poles so that continuous induction current is produced. It names the ring/cylinder construction, end-to-end connection, core, field relation, and continuous-current objective; it does not require only the Fig. 1 device.

Claim 2 (Independent)Alternate-current junction arrangement

Claim 2 separately claims the described arrangements that yield alternate or opposite currents rather than continuous output. In the specification, that includes the diametrically opposite, perpendicular junction connections through the shaft and insulated rod.

Claim 3 (Independent)Combined magneto-electric apparatus

Claim 3 claims the overall combinations shown and described for using electrical current, including industrial and physiological uses. Because it says substantially as described and illustrated, it is tied to the detailed apparatus and drawings rather than every future electrical machine.

IV. Mechanical Organ Breakdown

Endless bobbin and magnetic coreTerm: “large endless bobbin” → closed distributed armature winding on a magnetic core

A ring, cylinder, or other endless form carries a closed series of small, insulated coils around soft iron.

Junction conductors and rubbersTerm: “metal rubbers” → sliding electrical contacts or brushes

Springs, rollers, or other metal rubbers touch selected passing junction conductors to extract current.

Field magnets and motionTerm: “magneto-electric machine” → electromagnetic generator architecture

Permanent or electromagnets establish poles while a ring, disk, cylinder, chain, or sometimes the magnets rotate.

Alternate-current arrangementTerm: “alternate or opposite currents” → alternating-current output with orthogonal junction taps

The second construction can be reconnected to produce alternating rather than continuous current.

CLASSIC PATENTS DIGITAL ARCHIVE • PERMANENT EXHIBIT ID: us-120057-gramme-dynamo
classic-patents.com/patents/us-120057-gramme-dynamo
Original USPTO PDF
Classic Patents/US 120,057
Civil War & Industrial Acceleration (1860–1880)Magneto-Electric Machines & Dynamos

Gramme and d’Ivernois Endless-Bobbin Dynamo

US 120,057

Closed Series of Small Coils, Contact Rubbers, and Continuous or Alternate Induction Currents

Inventor(s)Zénobe Théophile Gramme, Eardley Louis Charles d’Ivernois
Grant DateOctober 17, 1871
Filing DateAugust 17, 1870
LocationParis, Empire of France
US 120,057 describes several magneto-electric machines built around a continuous series of small coils on a soft-iron ring, cylinder, disk, or moving chain. Contacts at selected coil junctions collect currents that the inventors describe as continuous or, in a stated alternate-current arrangement, opposite in direction. The grant issued October 17, 1871 after a United States application filed August 17, 1870.
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

The source’s problem is how to take induction from many small coils as a rotating magnetic relation changes, while avoiding a visibly interrupted output. Gramme and d’Ivernois connect the coil sections into an endless circuit, put an accessible conductor at each junction, and use contacts placed between unlike poles to take the like-directed currents that meet there. The patent also sets out a different connection for alternate current; it is not confined to a single later textbook form of the Gramme dynamo.
The Core Breakthrough Mechanism

Let a coil section move through magnetic flux. Its induced electromotive force follows Faraday’s relation E=−N dΦ/dt\mathcal{E}=-N\,d\Phi/dt. Around the closed series, sections before unlike poles induce currents whose directions bring like current together at selected junctions. The metal rubbers contact those junction conductors as they pass and take the combined current. The polarity depends on rotor direction, coil handedness, and the north-to-south order, conditions the specification expressly states. In the alternate-current version, two perpendicular pairs of diametrically opposite junctions are connected through the shaft and isolated rod.

Interactive Real-Time Physical Simulation

Drag to rotate · Pinch to zoom · Shared controls update the displayed model
INITIALIZING THREE.JS WEBGL SIMULATION...
Continuous-current collection from an endless ring winding.
Host-Model Telemetry/Computed Readout
Continuous-current collection from an endless ring winding
Induced e.m.f. (illustrative)
Normalized
100relative index[1]
Printed joined bobbins
Source
36junctions[1]
Collection continuity (idealized)
Normalized
97.2%overlap[1]
shaft rate → EMF index
100 index / rate
ts-fallback
Continuous Generated DC Voltage
∂V_gen / ∂ω_shaft (host sensitivity)
1.25 V / (rad·s⁻¹)
Illustrative shaft-rate factor1 relative
Coupled Transfer Dynamics · fs-couple
ts-fallback
shaft rateEMF index
+100index / rate
Interval ghosts
RPM1.0 rpm · [300, 1800]
Fidelity / MMS residual
Armature output current vs 1871 Paris test
model18.5 A
reference18.0 A
residual0.5 A
Coupled channels
shaft drive → ring armature1512 W
Dated scenarios

Detailed Component Architecture

1Endless bobbin and magnetic core
A ring, cylinder, or other endless form carries a closed series of small, insulated coils around soft iron.

Each small bobbin connects end-to-end to the next, leaving no free end in the large series. A conductor at every junction makes a moving electrical access point. The source permits a hollow or solid core and soft-iron wires or coils cemented together; it does not specify a universal turn count or modern performance figure. The induced voltage is described by E=−N dΦ/dt\mathcal{E}=-N\,d\Phi/dt.

19th-C. Term: large endless bobbinModern: closed distributed armature winding on a magnetic core
2Junction conductors and rubbers
Springs, rollers, or other metal rubbers touch selected passing junction conductors to extract current.

In the Fig. 1–3 construction, thirty-six coil junctions carry thirty-six conductors; springs S and S′ press on them. Fig. 4–6 has seventy-two conductors and four rubbers. The source calls these contacts rubbers, and makes their pressure adjustable by levers, screws, and springs. It does not describe them as an absent contact system.

19th-C. Term: metal rubbersModern: sliding electrical contacts or brushes
3Field magnets and motion
Permanent or electromagnets establish poles while a ring, disk, cylinder, chain, or sometimes the magnets rotate.

The figures show two, four, six, or more poles depending on construction. Coil direction, rotation direction, and pole arrangement set output polarity. The source also permits fixed rings with rotating interior magnets, or a rotating ring inside a fixed wound cylinder energized from part of its output.

19th-C. Term: magneto-electric machineModern: electromagnetic generator architecture
4Alternate-current arrangement
The second construction can be reconnected to produce alternating rather than continuous current.

Remove the C conductors and S springs, connect the shaft to one diametrically opposite pair of coil junctions, and connect the perpendicular pair to an isolated rod in the shaft as Fig. 11 shows. The frame/shaft and a rubber on that rod are the two stated alternating-current terminals. This is the entire condition, not merely a generic AC claim.

19th-C. Term: alternate or opposite currentsModern: alternating-current output with orthogonal junction taps
Engineering Principles & Equations

Governing Equations & Engineering Principles

Authored explanation paired with its stated mathematical relation

Continuous DC Generation & Multi-Segment Commutator Smoothing

Electromagnetics & GeneratorsClaim 1
Mathematical Governing Law
Terms:
Plain English DecoderHover or tap any highlighted phrase
The generated by the ring armature equals the product of , , and , with voltage ripple suppressed by the number of .
VDCV_{\text{DC}}
Direct Current Output Voltage
Steady direct electromotive force delivered to external load circuit without AC fluctuation
Volts (V)

Gramme was the first to achieve pure, ripple-free direct current suitable for industrial arc lighting and electroplating.

Physical Principle & Engineering Insight

Prior dynamos (like Pixii or Siemens shuttles) produced violent pulsating spikes that destroyed contacts. Gramme's toroidal ring acted as a continuous closed loop tapped at radial intervals, producing the world's first true smooth DC current.

Historical Context: US 120,057 transformed electricity from a laboratory curiosity into an industrial utility, launching the commercial electrical generation industry.

Toroidal Core Magnetic Flux Division Law

Electromagnetics & Magnetic CircuitsClaim 2
Mathematical Governing Law
Terms:
Plain English DecoderHover or tap any highlighted phrase
The is exactly half the , determined by across .
Φring\Phi_{\text{ring}}
Toroidal Semicircle Flux
Magnetic flux conducted through the upper and lower semi-annular iron ring branches
Webers (Wb)

Flux splits symmetrically at the neutral entry axis and recombines at the exit pole.

Physical Principle & Engineering Insight

The soft iron wire ring serves dual functions: it is the mechanical armature supporting the rotating copper windings, and simultaneously the magnetic yoke guiding flux around the interior void.

Historical Context: Gramme's machine was also reversible: feeding it DC current turned it into an electric motor, establishing the principle of electromechanical reversibility at the 1873 Vienna World's Fair.

Continuous Ring Armature Faraday Induction & Commutated Direct Current

Electrical Power & Magnetic InductionClaim 1
Mathematical Governing Law
Terms:
Plain English DecoderHover or tap any highlighted phrase
Generated continuous scales with , , and , while is suppressed by .
EDC\mathcal{E}_{\text{DC}}
Continuous Generated DC Voltage
Steady-state direct-current voltage delivered across positive and negative collector brushes (50 to 110 V50\text{ to }110\text{ V})
Volts (V)

Sums the individual Faraday voltages induced in all active coil bobbins across two parallel rotor branches.

Physical Principle & Engineering Insight

Prior to Zénobe Gramme's 1871 patent, electric dynamos produced jerky, violent alternating pulses that caused severe contact sparking and flickered wildly. Gramme wound insulated copper wire in a continuous, endless toroidal ring around an iron wire core, taking taps off every section to a radial multi-bar commutator. Because some coils were always crossing peak magnetic flux lines, the machine produced the first smooth, continuous direct current in history.

Historical Context: US 120057 launched the commercial electric power industry, powered the first citywide arc lighting grids in Paris and London, and demonstrated the electrical transmission of industrial motive power over long-distance transmission wires.

Faraday’s law of electromagnetic inductionAuthored Principle 1
Stated relationE=−N dΦ/dt\mathcal{E} = -N\,d\Phi/dt
A coil develops electromotive force when the magnetic flux linking it changes. The patent’s moving coils and changing relation to unlike magnetic poles are its physical way of producing that change.
Series connection and selected current collectionAuthored Principle 2
Stated relationVseries=∑iEiV_{\mathrm{series}} = \sum_i \mathcal{E}_i
The inventors join small bobbins end-to-end and select junctions where they say like currents meet. In a series path, compatible induced voltages add; the contact placement determines which combined output is taken.
Magnetic-circuit reluctanceAuthored Principle 3
Stated relationΦ=F/R\Phi = \mathcal{F}/\mathcal{R}
Soft iron gives the flux a much lower-reluctance route than air. The source repeatedly specifies soft-iron cores, links, and poles, while keeping moving members physically separate from field parts.

Interactive Schematic Sheet (Fig. 1)

Vertical projective view of the Fig. 1–3 machine; source drawing sheet 1.

1.00x
US 120,057 · FIG. 1NSContinuous Ring ArmatureSmooth DC Commutator Brushes
Tap any numbered pin2 Curated Callouts
Callout Pin Inspector

Select Any Numbered Pin

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Why It Still Matters

The patent documents a family of distributed-winding generator arrangements at a moment when electric power machinery was moving from laboratory apparatus toward industrial systems. Its legal and technical interest lies in its closed coil series, junction collection, and stated continuous/alternate-current variants, not in later numbers or performance claims absent from the grant.

Legal Claims Decoder (3 Numbered Claims)

Compare dense legalistic claims directly with decoded plain-English functional specifications.
Claim #1Independent Master Claim
1/3
Verbatim Historical Legal Text
“The employment, in magneto-electric machines, of one or more cylinders, rings, or large endless bobbins arranged and constructed in the manner as has been above described, viz., made into a circular or other suitable endless shape, and consisting of a series of small bobbins or wires enveloping a core of soft iron or other good magnetic material, and connected together end to end in a continuous series, the said endless large bobbin or bobbins or cylinders situated between or in opposition to the poles of fixed or movable permanent or electro-magnets, for the purpose of allowing the production of continuous induction-currents in the conducting-wires, strips, or ribbons of brass or other good conducting metal enveloping the magnetic material, in which wires, strips, or ribbons a continuous displacement of the magnetism takes place without demagnetizing.”
Plain English Engineering Translation
Claim 1 covers the stated endless closed series of small coils or conductive strips/ribbons on a magnetic core, positioned relative to fixed or moving permanent or electromagnet poles so that continuous induction current is produced. It names the ring/cylinder construction, end-to-end connection, core, field relation, and continuous-current objective; it does not require only the Fig. 1 device.
Key Protected Innovations:
Endless series of small bobbinsSoft-iron magnetic coreJunction-conductor current collectionContinuous induction-current arrangement
Historical Legal Impact:
This is the principal independent claim. Its language reaches rings, cylinders, and other suitable endless forms, and explicitly includes wire, strip, and ribbon conductors under the described field relationship.

The Historical Bottleneck

The grant addresses magneto-electric machines that needed a usable output from a moving magnetic relation. Its written solution divides the conductor into numerous connected coil sections and collects current at specific junctions rather than treating one coil as the entire armature.

Why Prior Art Failed

  • •A single winding and fixed terminals cannot provide the same selected-junction collection that the specification describes.
  • •The source distinguishes its continuous-current arrangement from circuit-breakers, pole-changers, and commutators, while still using metal rubbers to contact moving junction conductors.
The Breakthrough Insight
“Make the winding an endless series of small coils, expose a conductor at every coil junction, and select the points where like currents meet between unlike poles. The same architecture is then reconnected in one described case for alternating current.”

Patent Wars & Legal Litigations

Vs. Gramme Electrical Co. v. Arnoux & Hochhausen Electric Co., 17 F. 838 (C.C.S.D.N.Y. 1883)Infringement Challenge
Rival Claim & Defense:
Whether US 120,057’s term was constrained by the patentees’ Austrian patent under the 1870 Patent Act.
Litigation Conflict:
The court record identifies this grant, its August 17, 1870 US filing, the French patent of November 22, 1869, and the Austrian patent issued December 30, 1870.
Final Resolution & Judicial Outcome:
The court held that the US patent expired with the foreign patent having the shortest term that was granted before the US patent was granted.
After the Grant
The legal record in Gramme Electrical Co. v. Arnoux & Hochhausen Electric Co., 17 F. 838 (C.C.S.D.N.Y. 1883), considered the grant’s expiration in light of foreign-patent terms.
Civilizational Impact
The document preserves an early, unusually broad family of ring, cylinder, disk, chain, and concentric-winding machines at the foundation of industrial electric generation and motor practice.
Technological Lineage & Descent

The Polyphase Electric Grid

From Direct-Current Motors to Resonant Alternating Power Systems

The electrical revolution that replaced localized chemical galvanic cells and direct current with universal polyphase induction motors and high-voltage transmission.

1837First Rotary Electric Motor
US 132

Davenport Contact-Plate Electric Motor

Commutator-switched electromagnets creating continuous rotary motive torque.

1871Continuous DC DynamoThis Patent
US 120,057

Gramme and d’Ivernois Endless-Bobbin Dynamo

Closed-ring continuous toroidal armature eliminating pulsating current ripple.

1880High-Resistance Parallel Grid
US 223,898

Edison's High-Resistance Carbon Lamp

High-resistance carbon filament in high vacuum enabling parallel circuit distribution.

1888Rotating Magnetic Field
US 381,968

Tesla Progressive Alternating-Current Motor

Independent out-of-phase AC currents inducing rotor torque without brushes or sparks.

1897Resonant High-Frequency Transformer
US 593,138

Tesla's High-Potential Transformer

Air-core loosely coupled resonant LC circuits generating high-potential oscillations.