▁ ▁used ▁at ▁the ▁beginning ▁or ▁in ▁the ▁middle ▁of ▁a ▁word . ▁In ▁Spain , ▁the ▁change ▁to ▁use ▁a ▁round ▁s ▁everywhere ▁as ▁in ▁the ▁current ▁usage ▁was ▁mainly ▁accomplished ▁between ▁the ▁years ▁ 1 7 6 0 ▁and ▁ 1 7 6 6 ; ▁for ▁example , ▁the ▁multi - volume ▁España ▁S agr ada ▁made ▁the ▁switch ▁with ▁volume ▁ 1 6 ▁( 1 7 6 2 ). ▁▁ ▁From ▁ 1 7 4 1 ▁to ▁ 1 8 1 5 , ▁the ▁circum flex ▁was ▁used ▁over ▁v ow els ▁to ▁indicate ▁that ▁preceding ▁ ▁and ▁ ▁should ▁be ▁pron ounced ▁/ k / ▁and ▁/ ks / ▁respectively ▁and ▁not ▁/ t ʃ / ▁and ▁/ x /, ▁e . g . ▁, ▁. ▁ ▁The ▁use ▁of ▁acc ent ▁marks ▁in ▁publishing ▁var ies ▁with ▁different ▁historical ▁periods , ▁due ▁mainly ▁to ▁re forms ▁prom ul g ated ▁by ▁the ▁Spanish ▁Royal ▁Academy . ▁ ▁For ▁example , ▁many ▁of ▁the ▁words ▁that ▁are ▁today ▁standard ly ▁written ▁with ▁an ▁acc ent ▁mark ▁appeared ▁more ▁often ▁without ▁it ▁up ▁until ▁around ▁ 1 8 8 0 . ▁ ▁These ▁include ▁words ▁with ▁final ▁stress ▁ending ▁in ▁- n ▁ ▁( e . g . ▁, ▁, ▁, ▁, ▁— but ▁not ▁future - ten se ▁verb ▁forms ▁like ▁, ▁); ▁ver bs ▁in ▁the ▁imper fect ▁t ense ▁( e . g . ▁, ▁); ▁the ▁possess ives ▁m ío ▁and ▁m ía ; ▁and ▁the