,@@@,,,,,@                                          @@,,@@,@,,
@,,@,,,,@@                                          ,@,@,@@@,,
@,@@,,,@,,                                          @@@@@,,@,@
@@,@,,@@,@                                          ,,,,@,@@@,
,@@@,@,@@,                                          ,,,@@@,,@@
@,,@@@@,@@                  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!         @@@,,,@,,,
@@@@,,,@,,                                          ,,@,,@@,,@
,,,@,,@@,@                                          ,@@,@,@,@,
,,@@,@,@@,                                          @,@@@@@@@,
,@,@@@@,@@                                          @@,,,,,,@,
@@@,,,@@,@                                          ,@,,,,,@@,
,,@,,@,@@@                                          @@,,,,@,@@