Wood–Anderson torsion seismometer
E77001
The Wood–Anderson torsion seismometer is an early 20th-century mechanical seismograph designed to measure local earthquake ground motion with high sensitivity, forming the instrumental basis for the original Richter magnitude scale.
All labels observed (2)
| Label | Occurrences |
|---|---|
| Wood–Anderson torsion seismometer canonical | 3 |
| Wood–Anderson seismograph | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T614621 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Wood–Anderson torsion seismometer Context triple: [Richter magnitude scale, definedUsing, Wood–Anderson torsion seismometer]
-
A.
Richter magnitude scale
The Richter magnitude scale is a logarithmic scale used to quantify the amount of seismic energy released by an earthquake based on instrumental measurements.
-
B.
seismologist Harry Fielding Reid
Harry Fielding Reid was an American seismologist best known for formulating the elastic rebound theory, which explains how energy is stored and released in earthquakes.
-
C.
Alexanderson alternator
The Alexanderson alternator is an early high-frequency radio transmitter that generated continuous-wave signals using a rotating machine, playing a key role in long-distance wireless communication before vacuum-tube oscillators.
-
D.
Elster
Elster is a river in central Europe, primarily flowing through the German state of Saxony and its surrounding regions.
-
E.
Volta Laboratory
Volta Laboratory was an experimental research facility established in the late 19th century that became a key center for innovation in sound recording, telephony, and related communication technologies.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Wood–Anderson torsion seismometer Target entity description: The Wood–Anderson torsion seismometer is an early 20th-century mechanical seismograph designed to measure local earthquake ground motion with high sensitivity, forming the instrumental basis for the original Richter magnitude scale.
-
A.
Richter magnitude scale
The Richter magnitude scale is a logarithmic scale used to quantify the amount of seismic energy released by an earthquake based on instrumental measurements.
-
B.
seismologist Harry Fielding Reid
Harry Fielding Reid was an American seismologist best known for formulating the elastic rebound theory, which explains how energy is stored and released in earthquakes.
-
C.
Alexanderson alternator
The Alexanderson alternator is an early high-frequency radio transmitter that generated continuous-wave signals using a rotating machine, playing a key role in long-distance wireless communication before vacuum-tube oscillators.
-
D.
Elster
Elster is a river in central Europe, primarily flowing through the German state of Saxony and its surrounding regions.
-
E.
Volta Laboratory
Volta Laboratory was an experimental research facility established in the late 19th century that became a key center for innovation in sound recording, telephony, and related communication technologies.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
mechanical seismograph
ⓘ
scientific instrument ⓘ seismometer ⓘ torsion seismometer ⓘ |
| calibrationReferenceFor | Richter local magnitude ML ⓘ |
| component |
damped horizontal pendulum
ⓘ
lightweight mirror ⓘ photographic recording drum ⓘ torsion wire ⓘ |
| dampingType | aperiodic damping ⓘ |
| dataUsedFor | earthquake catalogs in early 20th century ⓘ |
| designedBy |
Harry O. Wood
ⓘ
John A. Anderson ⓘ |
| developedInPeriod | early 20th century ⓘ |
| eraOfMainUse |
1930s
ⓘ
mid-20th century ⓘ |
| field | seismology ⓘ |
| formsBasisOf |
Richter magnitude scale
ⓘ
surface form:
original Richter magnitude scale
|
| hasInfluenceOn | standardization of earthquake magnitude measurements ⓘ |
| hasKeyRoleIn | Richter magnitude scale ⓘ |
| hasOutput | seismogram ⓘ |
| historicalSignificance | provided first standardized instrumental basis for earthquake magnitude ⓘ |
| inspiredDevelopmentOf | later standardized short-period seismometers ⓘ |
| locationOfOriginalUse | Southern California ⓘ |
| measurementType | horizontal ground motion ⓘ |
| namedAfter |
Harry O. Wood
ⓘ
John A. Anderson ⓘ |
| notOptimizedFor | teleseismic (distant) earthquakes ⓘ |
| operatingPrinciple | torsional suspension of a horizontal pendulum ⓘ |
| optimizedFor | local and regional earthquakes ⓘ |
| orientation | typically installed in orthogonal horizontal components ⓘ |
| recordingMethod | optical recording on smoked paper or photographic paper ⓘ |
| relatedTo |
Richter magnitude scale
ⓘ
surface form:
Richter scale
local magnitude scale ⓘ |
| replacedBy | modern broadband seismometers ⓘ |
| requires | careful mechanical calibration ⓘ |
| requiresInstallation | rigid pier or foundation ⓘ |
| sensitivity | high sensitivity to local earthquakes ⓘ |
| standardInstrumentFor | original local magnitude (ML) scale ⓘ |
| status | largely obsolete ⓘ |
| typicalMagnification | about 2800 at 0.8 seconds ⓘ |
| typicalNaturalPeriod | approximately 0.8 seconds ⓘ |
| usedAt | Seismological Laboratory at Caltech ⓘ |
| usedBy | early 20th-century seismological observatories in California ⓘ |
| usedFor |
determining earthquake magnitude
ⓘ
measuring local earthquake ground motion ⓘ recording seismic waves ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Wood–Anderson torsion seismometer Description of subject: The Wood–Anderson torsion seismometer is an early 20th-century mechanical seismograph designed to measure local earthquake ground motion with high sensitivity, forming the instrumental basis for the original Richter magnitude scale.
Referenced by (4)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Wood–Anderson seismograph