Withafewfriendsintheuniversitycirclewhosharedtheseviews,weorganized,therefore,aco?perativegroupfortheeducationofourchildren,eachofustakingchargeoftheteachingofaparticularsubjecttoalloftheyoungpeople.Wewereallverybusywithotherthings,andthechildrenvariedinage.Nevertheless,thelittleexperimentthusmadewasveryinteresting.Withasmallnumberofclassesweyetsucceededinreunitingthescientificandliteraryelementsofadesirableculture.Thecoursesinsciencewereaccompaniedbypracticalexercisesinwhichthechildrentookgreatinterest.
Thisarrangement,whichlastedtwoyears,provedtobeverybeneficialformostofthechildren;itwascertainlysoformyelderdaughter.Followingthispreparation,shewasabletoenterahigherclassinoneofthecollegesofParis,andhadnodifficultyinpassingherbachelor's
examinationbeforetheusualage,afterwhichshecontinuedherscientificstudiesintheSorbonne.
Myseconddaughter,althoughnotbenefitingbyasimilararrangementforherearlierstudies,atfirstfollowedtheclassesofacollegeonlypartially,andlatercompletely.Sheshowedherselfagoodpupil,doingsatisfactoryworkinalldirections.
Iwantedverymuchtoassureformychildrenarationalphysicaleducation.Nexttooutdoorwalks,Iattachagreatimportancetogymnasticsandsports.Thissideofagirl'seducationisstillratherneglectedinFrance.Itookcarethatmychildrendidgymnasticsregularly.Iwasalsocarefultohavethemspendvacationseitherinthemountainsorattheseashore.Theycancanoeandswimverywellandarenotafraidofalongwalkorabicycleride.
Butofcoursethecareofmychildren'seducationwasonlyapartofmyduties,myprofessionaloccupationstakingmostofmytime.Ihavebeenfrequentlyquestioned,especiallybywomen,howIcouldreconcilefamilylifewithascientificcareer.Well,ithasnotbeeneasy;itrequiredagreatdealofdecisionandofself-sacrifice.However,thefamilybondhasbeenpreservedbetweenmeandmynowgrown-updaughters,andlifeismadebrighterbythemutualaffectionandunderstandinginourhome,whereIcouldnotsufferaharshwordorselfishbehavior.
In,whenIsucceededmyhusbandattheSorbonne,Ihadonlyaprovisionallaboratorywithlittlespaceandmostlimitedequipment.Afewscientistsandstudentshadalreadybeenadmittedtoworktherewithmyhusbandandme.Withtheirhelp,Iwasabletocontinuethecourseofresearchwithgoodsuccess.
In,IreceivedapreciousmarkofsympathyfromMr.AndrewCarnegie,whodonatedtomylaboratoryanannualincomeforresearchfellowshipswhichenabledsomeadvancedstudentsorscientiststodevotetheirwholetimetoinvestigation.Suchfoundationsareveryencouragingtothosewhoseinclinationsandtalentsaresuchastowarranttheirentiredevotiontoresearchwork.Theyoughttobemultipliedintheinterestofscience.
Asformyself,Ihadtodevoteagainagreatdealoftimetothepreparationofseveraldecigrammesofverypureradiumchloride.WiththisIachieved,in,anewdeterminationoftheatomicweightofradium,andinIwasabletoisolatethemetal.Theoperation,anextremelydelicateone,wasperformedwiththeassistanceofadistinguishedchemistbelongingtothelaboratorystaff.Ithasneverbeenrepeatedsincethattime,becauseitinvolvesaseriousdangeroflossofradium,whichcanbeavoidedonlywithutmostcare.SoIsawatlastthemysteriouswhitemetal,butcouldnotkeepitinthisstate,foritwasrequiredforfurtherexperiments.
Asforthepolonium,Ihavenotbeenabletoisolateit,itsquantityinthemineralbeingevenmuchlessthanthequantityofradium.However,veryconcentratedproloniumhasbeenpreparedinmylaboratory,andimportantexperimentshavebeenperformedwiththissubstance,concerningespeciallytheproductionofheliumbyradiationofpolonium.
Ihadtodevotespecialcaretotheimprovementofthemeasuringmethodsinthelaboratory.Ihavetoldhowimportantprecisemeasurementswereinthediscoveryofradium.Itisstilltobehopedthatefficientmethodsofquantitativedeterminationmayleadtonewdiscoveries.
Idevisedaverysatisfactorymethodfordeterminingthequantityofradiumbythemeansofaradioactivegasproducedbyitandcalled"emanation."Thismethod,frequentlyusedinmylaboratory,permitsofthemeasurementofverysmallquantitiesofradium(lessthanathousandthofamilligramme),withafairprecision.Moreimportantquantitiesareoftenmeasuredbytheirpenetratingradiation,namedGamma-rays.Forthiswealsopossessinmylaboratoryasuitableequipment.Itiseasierandmoresatisfactorytomeasuretheradiumbytheemittedrays,thantoweighitinabalance.However,thesemeasurementsrequirethedispositionofreliablestandards.Sothequestionofaradiumstandardhadtobetakenintocarefulconsideration.
Themeasurementsofradiumhadtobeestablishedonasolidbasis,forthebenefitoflaboratoriesandscientificresearch,which,ofcourse,isinitselfanimportantreason,andmoreover,thegrowingmedicalutilizationofthissubstancemadeitnecessarytocontroltherelativepurityofcommerciallyproducedradium.