Time travelers Timeline
-------------------------------------------------------------------------------->
|___________________|___________________|
Birth________ Builds machine_____Travels in Time
0 yrs.____________12 yrs______________24 yrs
1986 AD__________1998 AD____________1974 AD
Normal Timeline
--------------------------------------------------------------------------------->
|____________________|__________________|
Man Appears_________Born__________Builds Machine
24 yrs._____________0 yrs______________12 yrs
1974 AD__________1986 AD___________1986 AD
-------------------------------------------------------------------------------->
|___________________|___________________|
Birth________ Builds machine_____Travels in Time
0 yrs.____________12 yrs______________24 yrs
1986 AD__________1998 AD____________1974 AD
Normal Timeline
--------------------------------------------------------------------------------->
|____________________|__________________|
Man Appears_________Born__________Builds Machine
24 yrs._____________0 yrs______________12 yrs
1974 AD__________1986 AD___________1986 AD