Unit: metre
Data source: EPSG
Information source: US Army Map Service Technical Manual No. 7; 1943.
Revision date: 2013-01-17
Remarks: Original definition a=20926062 and b=20855121 (British) feet. Uses Clarke's 1865 inch-metre ratio of 39.370432 to obtain metres. (Metric value then converted to US survey feet for use in the US and international feet for use in Cayman Islands).
Definition: OGC Well Known Text
SPHEROID["Clarke 1866",6378206.4,294.978698213898, AUTHORITY["EPSG","7008"]]
Definition: OGC Well Known Text 2 (2019)
ELLIPSOID["Clarke 1866",6378206.4,294.978698213898, LENGTHUNIT["metre",1], ID["EPSG",7008]]
Definition: ESRI Well Known Text
SPHEROID["Clarke_1866",6378206.4,294.978698213898]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.5/projjson.schema.json", "type": "Ellipsoid", "name": "Clarke 1866", "semi_major_axis": 6378206.4, "semi_minor_axis": 6356583.8, "id": { "authority": "EPSG", "code": 7008 } }