Twowomen，especially，madethemselvesnotoriousatthistime，andwereinstrumentaltothedeathsofhundredsofindividuals。TheybothresidedinParis，andwerenamedLavoisinandLavigoreux。LikeSparsandTophania，ofwhomtheywereimitators，theychieflysoldtheirpoisonstowomenwhowantedtogetridoftheirhusbands；and，insomefewinstances，tohusbandswhowantedtogetridoftheirwives。Theirostensibleoccupationwasthatofmidwives。Theyalsopretendedtobefortune-tellers，andwerevisitedbypersonsofeveryclassofsociety。Therichandpoorthrongedaliketotheirmansardes，tolearnthesecretsofthefuture。Theirprophecieswereprincipallyofdeath。
Theyforetoldtowomentheapproachingdissolutionofhusbands，andtoneedyheirs，theendofrichrelatives，whohadmadethem，asByronexpressesit，“waittoo，toolongalready。“Theygenerallytookcaretobeinstrumentalinfulfillingtheirownpredictions。Theyusedtotelltheirwretchedemployers，thatsomesignoftheapproachingdeathwouldtakeplaceinthehouse，suchasthebreakingofglassorchina；
andtheypaidservantsconsiderablefeestocauseabreakage，asifbyaccident，exactlyattheappointedtime。Theiroccupationasmidwivesmadethemacquaintedwiththesecretsofmanyfamilies，whichtheyafterwardsturnedtodreadfulaccount。
Itisnotknownhowlongtheyhadcarriedonthisawfultradebeforetheywerediscovered。Detectionfinallyovertookthematthecloseoftheyear1679。Theywerebothtried，foundguilty，andburnedaliveonthePlacedeGreve，onthe22ndofFebruary，1680，aftertheirhandshadbeenboredthroughwithared-hotiron，andthencutoff。TheirnumerousaccomplicesinParisandintheprovinceswerealsodiscoveredandbroughttotrial。Accordingtosomeauthors，thirty，andtoothers，fiftyofthem，chieflywomen，werehangedintheprincipalcities。
Lavoisinkeptalistofthevisiterswhocametoherhousetopurchasepoisons。Thispaperwasseizedbythepoliceonherarrest，andexaminedbythetribunals。AmongthenameswerefoundthoseoftheMarshaldeLuxembourg，theCountessdeSoissons，andtheDuchessdeBouillon。TheMarshalseemsonlytohavebeenguiltyofapieceofdiscreditablefollyinvisitingawomanofthisdescription，butthepopularvoiceatthetimeimputedtohimsomethingmorethanfolly。