{"$schema":"https://proj.org/schemas/v0.7/projjson.schema.json","type":"GeographicCRS","name":"Unknown datum based upon the Plessis 1817 ellipsoid","datum":{"type":"GeodeticReferenceFrame","name":"Not specified (based on Plessis 1817 ellipsoid)","ellipsoid":{"name":"Plessis 1817","semi_major_axis":6376523,"inverse_flattening":308.64}},"coordinate_system":{"subtype":"ellipsoidal","axis":[{"name":"Geodetic latitude","abbreviation":"Lat","direction":"north","unit":"degree"},{"name":"Geodetic longitude","abbreviation":"Lon","direction":"east","unit":"degree"}]},"scope":"Not recommended.","area":"Not specified.","bbox":{"south_latitude":-90,"west_longitude":-180,"north_latitude":90,"east_longitude":180},"id":{"authority":"EPSG","code":4027},"remarks":"Use only in cases where geodetic datum is unknown."}