@,@,,@@,,,                                          @@@,,@@,@,
@@@@,@,@,,                                          ,,,@,@,@@@
,,,,@@@@@,                                          @,,@@@@@,,
,,,,@,,,,@                                          @@,@,,,,@,
,,,,@@,,,@                                          @,@@@,,,@@
@,,,@,@,,@                   rails                  ,@@,,@,,@,
@@,,@@@@,@                                          @@,@,@@,@@
,,@,@,,,@@                                          @,@@@@,@@,
,,@@@@,,@, @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @@@,,,@@,@
@,@,,,@,@@                                          ,,,@,,@,@@
,@@@,,@@@, @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @,,@@,@@@,
,@,,@,@,,@                                          ,@,@,@@,,@
@@@,@@@@,@                                          @@@@@@,@,@
,,,@@,,,@@ trains  are  so  constructed  that  they @,,,,,@@@@
@,,@,@,,@, have to follow a set path.  this path is @@,,,,@,,,
@@,@@@@,@@ called a "railway",  which is  comprised @,@,,,@@,,
@,@@,,,@@, of two metal rails, hence  its nickname. ,@@@,,@,@,
@@@,@,,@,@                                          @@,,@,@@@@
,,,@@@,@@@ because  the  low  friction between  the ,,@,@@@,,,
,,,@,,@@,, wheels of the train  and the rail metal, @,@@@,,@,,
,,,@@,@,@, there  are limits for how acute a  curve ,@@,,@,@@,
,,,@,@@@@@ can be, and even more so  for  how  much ,@,@,@@@,@
@,,@@@,,,, the  ground  under  the  rails  can   be ,@@@@@,,@@
,@,@,,@,,, sloped. thus a railway is often not  led ,@,,,,@,@,
,@@@@,@@,, on  top of hills, rather through them in @@@,,,@@@@
@@,,,@@,@, tunnels   (if   they   are   large),  or @,,@,,@,,,
@,@,,@,@@@            artificial chasms.            @@,@@,@@,,
@@@@,@@@,,                                          @,@@,@@,@,
@,,,@@,,@, there will  be trees on the  side of the ,@@,@@,@@@
,@,,@,@,@@ rails, but  not too close, or  they will ,@,@@,@@,,
,@@,@@@@@, be  cut  down by the  railway  janitors. ,@@@,@@,@,
,@,@@,,,,@ there  will be  plains,  and  bodies  of @@,,@@,@@@
@@@@,@,,,@                  water.                  @,@,@,@@,,
@,,,@@@,,@                                          @@@@@@@,@,
@@,,@,,@,@ trains go  by day  and  by  night. along ,,,,,,,@@@
,,@,@@,@@@       the way, there is information      ,,,,,,,@,,
,,@@@,@@,, scattered, often put  on top  of  poles, ,,,,,,,@@,
,,@,,@@,@, to be interpreted  by the train drivers. @,,,,,,@,@
@,@@,@,@@@ different  parts  of  the  railway  have @@,,,,,@@@
,@@,@@@@,,         different speed limits.          ,,@,,,,@,,
,@,@@,,,@,                                          @,@@,,,@@,
,@@@,@,,@@ sometimes, trains have to  stop and wait @@@,@,,@,@
@@,,@@@,@, for something to  happen, far away. this @,,@@@,@@@
,,@,@,,@@@ is signaled  by  red  or  green  lights. ,@,@,,@@,,
,,@@@@,@,,                                          ,@@@@,@,@,
,,@,,,@@@,                 @@@@@@@@                 ,@,,,@@@@@
@,@@,,@,,@                                          @@@,,@,,,,
@@@,@,@@,@ many people  follow  the rails by  foot. @,,@,@@,,,
@,,@@@@,@@ often this  proves  to  be  the  shorter ,@,@@@,@,,
@@,@,,,@@, path  between  two points. however  this ,@@@,,@@@,
@,@@@,,@,@ is  frowned  upon,   and  very  impolite ,@,,@,@,,@
,@@,,@,@@@        toward the train drivers!         @@@,@@@@,@
@@,@,@@@,,                                          ,,,@@,,,@@
,,@@@@,,@,                                          ,,,@,@,,@,
,,@,,,@,@@                                          @,,@@@@,@@
@,@@,,@@@,                                          ,@,@,,,@@,
@@@,@,@,,@                                          ,@@@@,,@,@
,,,@@@@@,@                                          ,@,,,@,@@@