,writingnumbersonachalkboard.

    "Thatsright,andyouseethis?"Shepoihedateomark,whiinasemicircle:MONFEB1350AM."ThatswhenyourShakespeareputitinthemailbox.OnaMon.ThatmeansMondaymiswheampedit."

    "So,todayisValentinesDay?HappyValentinesDay."

    "No,Aniday.Youhavetolearhesignsandfigureitout.Dedu.HowcouldtodaybeValentinesDayiftodayisaMonday?Howwefierthedaybeforeitislost?IfIfoueryesterday,andtodayisMonday,howcouldtodaybeValentinesDay?"

    Iwasfusedandtired.Myheadached.

    "FebruarythirteenthwaslastMonday.Ifthiscardhadbeenoutformorethawouldberuinedbynow.Ifoundityesterdayandbroughtittoyou.Yesterdaywasaquietday—notmanycars—aSunday.TodaymustbetheMonday."

    Shemademequestionmyabilitytoreasonatall.

    "Itssimple.TodayisMonday,February20,1950.Youdoneedadar."Sheheldoutherhandformypencil,whichIgladlycededher.Onthebackofthecard,shedrewsevenboxesinarowandlabeledS-M-T-W-T-F-Sforthedaysoftheweek.Thensheprintedallthemonthsoftheyearinanontheside,aheoppositeside,thenumeralsfrom1to31.Asshedrewthem,shequizzedmeonthepropernumberofdaysineath,singingafamiliarsongtohelpmeremember,butwefotaboutleapyears,whichwouldthrowmeoffintime.Fromherpocket,shetookthreeroualcirclestodemonstratethatifIwaokeeptrae,allIwouldhavetodowouldbetomovethediskstothespathedareachm,rememberingtostartoverattheendoftheweekandmonth.

    Speckwouldoftenshowmerovedtobetheobviousanswer,forwhiobodyelsehadtheclarityofimaginationaivity.Atsuentsofinsi