,FRANCES ;,V4 ,SPENCE "<;N;E ,BILAS2 ,MARCH #B1 #AIBB ,JULY #AH1 #BJAB">1 KNOWN PROFESSIONALLY AS ,FRAN ,BILAS1 WAS AN ,AMERICAN MATHEMATICIAN1 PHYSICIST1 AND COMPUTER SCIENTIST ONE OF THE SIX ORIGINAL PROGRAMMERS OF ,,ENIAC1 THE FIRST GENERAL-PURPOSE ELECTRONIC DIGITAL COMPUTER1 AND THEREFORE ONE OF THE FIRST COMPUTER PROGRAMMERS IN HISTORY4..>.>..>.> ,WITHIN THE SIX1 ,BILAS'S DOCUMENTED CONTRIBUTIONS ARE UNUSUALLY EASY TO MAP ONTO THE MODERN PROFESSION3 SHE IS CREDITED WITH AUTHORING ,,ENIAC'S FIRST SORT ROUTINE AND CONSTRUCTING THE MACHINE'S PROGRAM-CHECK MECHANISMS SYSTEMATIC PROCEDURES FOR VERIFYING THAT A RUN WAS BEHAVING CORRECTLY AND WAS ONE OF THE OPERATORS OF THE MACHINE AT ITS PUBLIC UNVEILING IN ,FEBRUARY #AIDF1 WHEN THE FIRST PUBLIC PHOTOGRAPHS OF PROGRAMMING-IN-PROGRESS WERE MADE4..>.>..>.> ,EARLY LIFE AND EDUCATION ,FRANCES ;,V4 ,BILAS WAS BORN IN ,PHILADELPHIA1 ,PENNSYLVANIA1 THE SECOND OF FIVE SISTERS4 ,BOTH OF HER PARENTS WORKED IN EDUCATION HER FATHER AS AN ENGINEER FOR THE ,PHILADELPHIA ,PUBLIC ,SCHOOL SYSTEM1 HER MOTHER AS A TEACHER A HOUSEHOLD IN WHICH SCHOOLING WAS TREATED AS THE FAMILY BUSINESS4.1 BIOGRAPHICAL MATERIAL ON ,BILAS.>.> ,SHE ATTENDED THE ,SOUTH ,PHILADELPHIA ,HIGH ,SCHOOL FOR ,GIRLS1 GRADUATING IN ,JANUARY #AICH1 AND BEGAN UNIVERSITY STUDY AT ,TEMPLE ,UNIVERSITY4 ,WHEN ,CHESTNUT ,HILL ,COLLEGE AWARDED HER A FULL SCHOLARSHIP SHE TRANSFERRED THERE1 MAJORING IN MATHEMATICS WITH A MINOR IN PHYSICS A COMBINATION THAT PLACED HER AMONG THE SMALL NUMBER OF ,AMERICAN WOMEN THEN RECEIVING SERIOUS TECHNICAL TRAINING4 ,SHE GRADUATED IN #AIDB4 ,AMONG HER ,CHESTNUT ,HILL CLASSMATES WAS A FELLOW MATHEMATICS MAJOR NAMED ,KATHLEEN ,MC,NULTY2 THE TWO WOULD MEET AGAIN ON THE MOST CONSEQUENTIAL PROJECT OF THEIR LIVES4..>.> ,SHE LATER RETURNED TO ,TEMPLE FOR GRADUATE WORK IN MATHEMATICS4..>.> ,THE FIRING-TABLE CORPS ,BILAS ENTERED THE WORKFORCE IN THE MIDDLE OF THE ,SECOND ,WORLD ,WAR1 INTO THE ONE TECHNICAL OCCUPATION THEN OPEN TO WOMEN WITH HER TRAINING3 THE ,UNITED ,STATES ,ARMY'S HUMAN-COMPUTER CORPS AT THE ,UNIVERSITY OF ,PENNSYLVANIA'S ,MOORE ,SCHOOL OF ,ELECTRICAL ,ENGINEERING4 ,THE CORPS SEVERAL DOZEN WOMEN OFFICIALLY TITLED 8COMPUTERS0 PRODUCED ARTILLERY FIRING TABLES FOR THE ,ARMY'S ,BALLISTIC ,RESEARCH ,LABORATORY1 COMPUTING TRAJECTORIES ON ,MONROE DESK CALCULATORS AND1 WHEN AVAILABLE1 ON THE ,MOORE ,SCHOOL'S DIFFERENTIAL ANALYZER4 ,THE WORK WAS MATHEMATICALLY DEMANDING AND OPERATIONALLY RELENTLESS3 A SINGLE TABLE REPRESENTED HOURS TO DAYS OF CONTINUOUS COMPUTATION1 AND THE ,ARMY NEEDED THEM IN VOLUME4.2 ,HAIGH ET AL41 ,,ENIAC IN ,ACTION "<#BJAF">.>.> ,LIKE MOST OF THE CORPS1 ,BILAS FOUND THE LABOR AS MONOTONOUS AS IT WAS ESSENTIAL4 ,WHAT THE POSITION PROVIDED AND WHAT NO CLASSROOM COULD WAS DAILY PRACTICE IN DECOMPOSING A PHYSICAL PROBLEM INTO A FIXED SEQUENCE OF ELEMENTARY ARITHMETIC OPERATIONS3 THE PRECISE MENTAL DISCIPLINE THAT WOULD SHORTLY BE CALLED PROGRAMMING4..>.> ,,ENIAC ,SELECTION AND THE ABSENCE OF ANY METHOD ,IN #AIDE THE ,ARMY CIRCULATED A CALL FOR SIX VOLUNTEERS TO STAFF A CLASSIFIED MACHINE UNDER CONSTRUCTION AT THE ,MOORE ,SCHOOL4 ,BILAS VOLUNTEERED AND WAS SELECTED1 TOGETHER WITH ,KAY ,MC,NULTY1 ,BETTY ,JENNINGS1 ,BETTY ,SNYDER1 ,MARLYN ,WESCOFF1 AND ,RUTH ,LICHTERMAN THE GROUP SUBSEQUENTLY KNOWN AS THE ,,ENIAC SIX1 AND IN HINDSIGHT AS THE FIRST PROGRAMMERS4..>.> ,THE MACHINE1 ,,ENIAC "<,ELECTRONIC ,NUMERICAL ,INTEGRATOR AND ,COMPUTER">1 WAS ELECTRONIC BUT NOT PROGRAMMABLE IN ANY MODERN SENSE4 ,IT HAD NO STORED INSTRUCTION SET1 NO PROGRAMMING LANGUAGE1 AND NO DOCUMENTATION2 A COMPUTATION WAS REALIZED BY PHYSICALLY CONFIGURING THE HARDWARE ROUTING SIGNALS BETWEEN UNITS THROUGH PLUGBOARDS WITH HUNDREDS OF PATCH CABLES1 SETTING THOUSANDS OF SWITCHES1 AND SEQUENCING THE MACHINE'S TWENTY ACCUMULATORS INTO A PLAN OF EXECUTION4 ,THE SIX WERE INITIALLY FURNISHED ONLY WITH THE ENGINEERS' BLOCK DIAGRAMS1 FROM WHICH THEY RECONSTRUCTED THE MACHINE'S LOGICAL BEHAVIOR BEFORE BEING ADMITTED TO THE ROOM WHERE IT STOOD4 ,THE TECHNIQUES THEY DEVELOPED UNDER THESE CONDITIONS PLANNING COMPUTATIONS ON PAPER BY FLOWCHART1 TRACKING MACHINE STATE SYSTEMATICALLY1 AND VERIFYING CONFIGURATIONS BEFORE COMMITTING TO THEM CONSTITUTE THE EARLIEST RECORDED PRACTICE OF PROGRAMMING AS A DISTINCT DISCIPLINE4..>.> ,SORT ROUTINES AND PROGRAM CHECKS ,WITHIN THE TEAM1 TWO OF ,BILAS'S SPECIFIC CONTRIBUTIONS ARE DOCUMENTED IN THE HISTORICAL RECORD AND DESERVE EMPHASIS BECAUSE THEY MAP DIRECTLY ONTO PRACTICES THAT REMAIN CENTRAL TO THE FIELD4 ,THE FIRST IS ,,ENIAC'S INITIAL SORT ROUTINE4 ,ORDERING DATA IS AMONG THE MOST BASIC REQUIREMENTS OF COMPUTATION FIRING TABLES1 INVENTORY1 AND ANALYSIS ALL REDUCE TO IT AND ,BILAS IS CREDITED WITH AUTHORING THE FIRST PROGRAM ON THE MACHINE TO PERFORM IT EFFECTIVELY THE FIRST SORTING ALGORITHM EXECUTED ON A GENERAL-PURPOSE ELECTRONIC COMPUTER4 "<,THE RECORD NEEDS A CAVEAT HERE3 ,BETTY ,SNYDER ,HOLBERTON IS ALSO WIDELY DESCRIBED AS INVENTING THE FIRST SORT ROUTINE1 REFERRING TO HER LATER ,SORT,MERGE ,GENERATOR WORK ON ,,UNIVAC2 ,BILAS'S CLAIM IS THE EARLIER ONE1 ON ,,ENIAC ITSELF4">..>.> ,THE SECOND1 AND ARGUABLY MORE CONSEQUENTIAL1 IS HER CONSTRUCTION OF THE MACHINE'S PROGRAM-CHECK MECHANISMS4 ,,ENIAC WAS PHYSICALLY UNRELIABLE IN WAYS MODERN HARDWARE IS NOT3 VACUUM TUBES FAILED ON A CYCLE MEASURED IN DAYS1 MARGINAL CONNECTIONS DRIFTED1 AND A MALFORMED SIGNAL PRODUCED NOT A CRASH BUT CONFIDENTLY INCORRECT OUTPUT4 ,KLEIMAN'S RESEARCH CREDITS ,BILAS WITH DEVISING SYSTEMATIC CHECKS PROCEDURES INTERLEAVED WITH A RUN TO CONFIRM THAT INTERMEDIATE STATE REMAINED CORRECT AND TO LOCALIZE THE FAULT WHEN IT DID NOT4 ,IN CONTEMPORARY TERMS THIS IS THE ANCESTRAL FORM OF RUNTIME VALIDATION1 AUTOMATED TESTING1 AND FAULT ISOLATION2 ON ,,ENIAC IT WAS SIMPLY HOW A COMPUTATION BECAME TRUSTWORTHY ENOUGH TO BE BELIEVED4.2 ,,ENIAC IN ,ACTION "<#BJAF">.>.> . AND ,FRANCES ,BILAS " OPERATING ,,ENIAC'S MAIN CONTROL PANEL1 ;C4 #AIDF THE MOST WIDELY REPRODUCED IMAGE OF THE ,,ENIAC SIX AT WORK4 ,U4,S4 ,ARMY PHOTOGRAPH1 PUBLIC DOMAIN4.> ,THE ,FEBRUARY #AIDF DEMONSTRATION ,ON ,FEBRUARY #AD#AE1 #AIDF1 THE ,ARMY PRESENTED ,,ENIAC TO THE PRESS THE FIRST PUBLIC DISCLOSURE THAT A FULLY ELECTRONIC GENERAL-PURPOSE COMPUTER EXISTED4 ,THE DEMONSTRATION'S CENTERPIECE WAS A SIXTY-SECOND ARTILLERY TRAJECTORY COMPUTED IN LESS TIME THAN THE SHELL WOULD HAVE REQUIRED TO FLY IT4 ,BILAS SERVED AS ONE OF THE MACHINE'S OPERATORS FOR THE EVENT1 AND IT IS HER FACE WITH ,BETTY ,JENNINGS AT THE MAIN CONTROL PANEL THAT APPEARS IN THE ERA'S MOST FREQUENTLY REPRODUCED PHOTOGRAPHS4.2 CONTEMPORARY PRESS COVERAGE OF THE UNVEILING.>.> ,THE COVERAGE ITSELF RECORDED THE ERA'S MISREADING3 THE WOMEN AT THE PANELS WERE VARIOUSLY CROPPED FROM PHOTOGRAPHS1 OMITTED FROM CAPTIONS1 OR DESCRIBED TO REPORTERS AS DECORATIVE STAFF4 ,THE MACHINE'S HARDWARE DESIGNERS1 ,ECKERT AND ,MAUCHLY1 WERE NAMED2 ITS PROGRAMMERS WERE NOT4..>.> ,BILAS CONTINUED TO WORK ON ,,ENIAC AFTER THE WAR'S END1 AS THE MACHINE'S PROGRAMMING WORK MOVED WITH IT TO THE ,BALLISTIC ,RESEARCH ,LABORATORY AT ,ABERDEEN ,PROVING ,GROUND1 ,MARYLAND4..>.> ,MARRIAGE AND LEAVING THE FIELD ,IN #AIDG SHE MARRIED ,HOMER ;,W4 ,SPENCE1 AN ENLISTED ,ARMY ENGINEER ASSIGNED TO THE ,,ENIAC GROUP AT THE ,MOORE ,SCHOOL1 WHO MOVED WITH THE MACHINE TO ,ABERDEEN AND LATER BECAME HEAD OF ITS ,COMPUTER ,RESEARCH ,BRANCH4 ,SHE LEFT GOVERNMENT EMPLOYMENT SHORTLY AFTER THE MARRIAGE IN A PERIOD WHEN WOMEN IN FEDERAL SERVICE ROUTINELY EXITED TECHNICAL POSTS UPON MARRYING AND BEGAN RAISING A FAMILY2 THE ,SPENCES HAD THREE SONS1 ,JOSEPH1 ,RICHARD1 AND ,WILLIAM4..>.> ,HER PROGRAMMING CAREER ENDED WITH THE RESIGNATION4 ,THE COMMERCIAL ERA OF THE PROFESSION SHE HAD HELPED CREATE THE ,ECKERT,MAUCHLY ,COMPUTER ,CORPORATION1 WHICH PRODUCED ,,BINAC AND THEN ,,UNIVAC1 THE FIRST COMMERCIAL COMPUTER IN THE ,UNITED ,STATES WENT FORWARD WITH HER COLLEAGUES ,BETTY ,JENNINGS AND ,BETTY ,SNYDER1 BUT ,SPENCE NEVER RETURNED TO FULL-TIME WORK IN COMPUTING4 ,IN LATER DECADES SHE LIVED LARGELY OUTSIDE THE FIELD'S PUBLIC VIEW1 A PATTERN SHARED BY MOST OF THE SIX1 WHOSE CONTRIBUTIONS WERE SUBSTANTIALLY FORGOTTEN BY THE INDUSTRY THEY HAD FOUNDED4.2 ,KLEIMAN1 ,PROVING ,GROUND "<#BJBB">.>.> ,RECOGNITION AND DEATH ,INSTITUTIONAL RECOGNITION ARRIVED HALF A CENTURY LATE4 ,IN #AIIG THE SIX ,,ENIAC PROGRAMMERS WERE INDUCTED COLLECTIVELY INTO THE ,WOMEN IN ,TECHNOLOGY ,INTERNATIONAL ,HALL OF ,FAME THE FIRST MAJOR ACKNOWLEDGMENT THAT PROGRAMMING'S FOUNDING GENERATION WAS FEMALE4 ,BILAS LIVED TO SEE THE HISTORICAL CORRECTION GATHER PACE1 AS ,KATHY ,KLEIMAN'S RESEARCH1 HER BOOK ,PROVING ,GROUND "<#BJBB">1 AND HER DOCUMENTARY ,THE ,COMPUTERS "<#BJAD"> RESTORED THE SIX TO THE RECORD UNDER THEIR OWN NAMES4..>.> ,FRANCES ,BILAS ,SPENCE DIED ON ,JULY #AH1 #BJAB1 AT THE AGE OF NINETY4 ,SHE IS BURIED AT THE ,CEMETERY OF THE ,HOLY ,ROOD IN ,WESTBURY1 ,NEW ,YORK4 . ,ASSESSMENT ,BILAS'S HISTORICAL POSITION RESTS ON TWO FACTS THAT NO LONGER REQUIRE ARGUMENT4 ,FIRST1 SHE WAS PRESENT AT THE CREATION3 THE ,,ENIAC SIX INVENTED PROGRAMMING PRACTICE IN THE ABSENCE OF ANY PRECEDENT FOR IT4 ,SECOND1 HER OWN DOCUMENTED WORK THE SORT ROUTINE AND PROGRAM CHECKS CREDITED TO HER ADDRESSED THE TWO QUESTIONS EVERY WORKING PROGRAMMER STILL ANSWERS DAILY3 HOW DO ,I MAKE THE MACHINE TRANSFORM THE DATA1 AND HOW DO ,I PROVE IT DID SO CORRECTLY4 ,THE SECOND QUESTION1 LARGELY HER SPECIALTY1 IS THE FIELD'S LEAST CELEBRATED DISCIPLINE AND ITS MOST ESSENTIAL ONE4 ,THAT A MONUMENT TO TESTING SHOULD BELONG TO A WOMAN WHOSE OWN WORK WAS FOR DECADES UNTESTED BY HISTORY IS A SYMMETRY THE RECORD HAS ONLY RECENTLY BEGUN TO CORRECT4 ,SEE ALSO - ,THE FIRST PROGRAMMERS THE STORY OF ALL SIX - ,KAY ,MC,NULTY ,BETTY ,JENNINGS ,BETTY ,SNYDER ,MARLYN ,WESCOFF ,RUTH ,LICHTERMAN THE OTHER FIVE - ,,UNIVAC ,I THE COMMERCIAL SUCCESSOR HER COLLEAGUES HELPED PROGRAM - ,HISTORY OF ,PROGRAMMING - ,JO,ANN ;,H4 ,MORGAN THE WOMAN WHO FOLLOWED THEM INTO THE LAUNCH ROOM1 A GENERATION LATER ,REFERENCES #A4 ,KLEIMAN1 ,KATHY4 ,PROVING ,GROUND3 ,THE ,UNTOLD ,STORY OF THE ,SIX ,WOMEN ,WHO ,PROGRAMMED THE ,WORLD'S ,FIRST ,MODERN ,COMPUTER "<,GRAND ,CENTRAL1 #BJBB">4 #B4 ,HAIGH1 ,THOMAS1 ,MARK ,PRIESTLEY1 AND ,CRISPIN ,ROPE4 ,,ENIAC IN ,ACTION3 ,MAKING AND ,REMAKING THE ,MODERN ,COMPUTER "<,,MIT ,PRESS1 #BJAF">4 #C4 ,EVANS1 ,CLAIRE ;,L4 ,BROAD ,BAND3 ,THE ,UNTOLD ,STORY OF THE ,WOMEN ,WHO ,MADE THE ,INTERNET "<,PORTFOLIO1 #BJAH">4 #D4 ,WOMEN IN ,TECHNOLOGY ,INTERNATIONAL ,HALL OF ,FAME #AIIG INDUCTION OF THE ,,ENIAC PROGRAMMERS4 #E4 ,KLEIMAN1 ,KATHY "4 ,THE ,COMPUTERS DOCUMENTARY ON THE ,,ENIAC SIX "<#BJAD">4 #F4 ,U4,S4 ,ARMY PHOTOGRAPHS OF ,,ENIAC AND ITS OPERATORS1 #AIDE#DF "4