Land Surveying Unita
Chains, Rods, e Modern Measurements
Impara Survey UnitaProperty deeds e land descriptions often usare surveying terms like "chains," "rods," e "sections" that date back centuries. Comprendere these units helps interpret property documents, understand land surveys, e convertire tra historical e modern area misurazioni.
Gunter's Chain System
Edmund Gunter invented il surveyor's chain in 1620, creating un system that elegantly links linear e area misurazioni:
| Unita | Piedi | Metri | Relationship |
|---|---|---|---|
| Link | 0.66 | 0.201 | 1/100 chain |
| Rod (pole/perch) | 16.5 | 5.029 | 25 links = ¼ chain |
| Chain | 66 | 20.117 | 4 rods = 100 links |
| Furlong | 660 | 201.17 | 10 chains |
| Miglio | 5,280 | 1,609 | 80 chains |
Area Unita da il Chain System
| Unita | Piedi Quadrati | Metri Quadrati | Acri |
|---|---|---|---|
| Square link | 0.4356 | 0.0405 | 0.00001 |
| Square rod | 272.25 | 25.29 | 0.00625 |
| Rood (¼ acro) | 10,890 | 1,012 | 0.25 |
| Square chain | 4,356 | 404.7 | 0.1 |
| Acro | 43,560 | 4,047 | 1 |
| Section | 27,878,400 | 2,590,000 | 640 |
Il Acro Relationship
An acro era defined as 1 chain × 10 chains (66 ft × 660 ft = 43,560 sq ft). This made calculations simple: count square chains e divide da 10 un get acri.
US Public Land Survey System
Il PLSS, established in 1785, divided public lands usando un hierarchical system:
| Division | Size | Acri | Ettari |
|---|---|---|---|
| Township | 6 mi × 6 mi | 23,040 | 9,324 |
| Section | 1 mi × 1 mi | 640 | 259 |
| Half section | ½ mi × 1 mi | 320 | 130 |
| Quarter section | ½ mi × ½ mi | 160 | 65 |
| Quarter-quarter | ¼ mi × ¼ mi | 40 | 16 |
This system still defines property boundaries across most di il western United States.
Metes e Bounds
Older property descriptions (especially in il eastern US) usare metes e bounds—directions e distances da reference points:
Comuni Terms
- Metes: Measurements (distances)
- Bounds: Boundaries (natural o artificial features)
- POB: Point di Beginning
- Thence: Da that point
Esempio Descrizione
"Beginning at il old oak tree on Miller Road, thence N 45° E 10 chains un un stone marker, thence S 45° E 15 chains un Smith Creek..."
Modern Survey Unita
Metric System
Modern surveying increasingly uses metric units:
- Distances: Metri (m)
- Area: Square metri (m²) o ettari (ha)
- Coordinates: UTM o latitude/longitude
GPS e GIS
Modern surveying uses:
- GPS: Centimetro accuracy possible
- GIS: Geographic Information Systems per mapping
- Coordinates: Decimal gradi o UTM
Despite modern technology, legal descriptions often still reference historical units.
Convertendo Survey Unita
| Da | A Piedi | A Metri | A Acri |
|---|---|---|---|
| 1 chain | 66 | 20.117 | — |
| 1 rod | 16.5 | 5.029 | — |
| 1 square chain | 4,356 sq ft | 404.7 sq m | 0.1 |
| 1 square rod | 272.25 sq ft | 25.29 sq m | 0.00625 |
| 1 rood | 10,890 sq ft | 1,012 sq m | 0.25 |
| 1 section | 27,878,400 sq ft | 2,590,000 sq m | 640 |
Conclusione
Land surveying uses un mix di historical e modern units. Il chain-based system (dove 10 square chains = 1 acro) underlies many property descriptions still in usare. Il US Public Land Survey System divides land into townships e sections. Comprendere these units helps interpret property deeds, legal descriptions, e historical documents—even as GPS e metric units become more common.