▁to ▁use ▁a ▁b aton ▁and ▁also ▁invent ing ▁re he ars al ▁letters , ▁which ▁are ▁placed ▁period ically ▁throughout ▁a ▁piece ▁of ▁sheet ▁music ▁so ▁that ▁a ▁conduct or ▁may ▁save ▁time ▁by ▁asking ▁the ▁or chestra ▁or ▁sing ers ▁to ▁start ▁playing ▁" from ▁letter ▁C ", ▁for ▁example . ▁ ▁In ▁addition ▁to ▁musical ▁works , ▁Spo hr ▁is ▁remembered ▁particularly ▁for ▁his ▁Vi olin schule ▁( The ▁Vi olin ▁School ), ▁a ▁treat ise ▁on ▁viol in ▁playing ▁which ▁cod ified ▁many ▁of ▁the ▁latest ▁adv ances ▁in ▁viol in ▁technique , ▁such ▁as ▁the ▁use ▁of ▁sp ic c ato . ▁ ▁It ▁became ▁a ▁standard ▁work ▁of ▁instruction . ▁In ▁addition , ▁he ▁wrote ▁an ▁entertain ing ▁and ▁inform ative ▁aut obi ography , ▁published ▁post hum ously ▁in ▁ 1 8 6 0 . ▁A ▁museum ▁is ▁devoted ▁to ▁his ▁memory ▁in ▁K ass el . ▁ ▁According ▁to ▁Rey ▁M . ▁Long year , ▁Spo hr ' s ▁best ▁works ▁were ▁ha iled ▁by ▁many ▁of ▁his ▁contempor aries ▁as ▁qu int ess entially ▁Rom antic ▁and ▁inherited ▁by ▁M end els so hn . ▁ ▁Selected ▁record ings ▁Opera ▁ ▁Fa ust ▁( W o O ▁ 5 1 ) ▁H ille vi ▁Martin pel to , ▁Franz ▁Haw l ata ▁and ▁Bo ▁Sk ov hus . ▁Klaus ▁Ar p ▁conduct ing ▁the ▁S WR ▁Radio ▁Orchestra , ▁Kais ers la ut ern . ▁Label : ▁Cap ric cio , ▁ 1 9