format
The format is:
Formal class 'SpatialLinesDataFrame' [package "sp"] with 4 slots
..@ data :'data.frame': 134 obs. of 2 variables:
.. ..$ ScaleRank : int [1:134] 1 0 0 0 1 1 1 0 1 1 ...
.. ..$ FeatureCla: Factor w/ 2 levels "Coastline","Country": 1 1 1 1 1 1 1 1 1 1 ...
.. ..- attr(*, "data_types")= chr [1:2] "N" "C"
..@ lines :List of 134
.. ..$ :Formal class 'Lines' [package "sp"] with 2 slots
.. .. .. ..@ Lines:List of 1
.. .. .. .. ..$ :Formal class 'Line' [package "sp"] with 1 slots
.. .. .. .. .. .. ..@ coords: num [1:11, 1:2] -164 -163 -161 -160 -159 ...
.. .. .. ..@ ID : chr "0"
.. .. [list output truncated]
..@ bbox : num [1:2, 1:2] -180 -85.6 180 83.6
.. ..- attr(*, "dimnames")=List of 2
.. .. ..$ : chr [1:2] "x" "y"
.. .. ..$ : chr [1:2] "min" "max"
..@ proj4string:Formal class 'CRS' [package "sp"] with 1 slots
.. .. ..@ projargs: chr NAsource
http://www.naturalearthdata.com/downloads/110m-physical-vectors/