, ▁Jen ner ' s ▁role ▁in ▁its ▁introduction ▁was ▁firm ly ▁established ▁and ▁Pear son ▁played ▁little ▁further ▁part . ▁However , ▁his ▁role ▁in ▁the ▁introduction ▁of ▁small po x ▁v acc ine ▁was ▁exam ined ▁in ▁detail ▁much ▁later ▁when ▁controvers y ▁arose ▁over ▁the ▁origin ▁of ▁v acc in ia ▁virus , ▁the ▁active ▁constitu ent ▁of ▁small po x ▁v acc ine . ▁▁▁▁ ▁No . ▁ 5 2 ▁Le ic ester ▁Square ▁ ▁For ▁ 2 0 ▁years , ▁between ▁the ▁ages ▁of ▁ 3 4 ▁and ▁ 5 4 , ▁from ▁ 1 7 8 5 – 1 8 0 5 , ▁Dr . ▁Pear son ▁lived ▁at ▁ 5 2 ▁Le ic ester ▁Square . ▁His ▁prede cess ors ▁there ▁included ▁Sir ▁Paul ▁Ry ca ut , ▁the ▁trav eller , ▁diplom at , ▁and ▁historian ▁of ▁Turkey , ▁ 1 6 7 9 - c . ▁ 1 6 8 4 ; ▁Justice ▁Robert ▁Perry man ▁or ▁Per r ism ore , ▁ 1 7 0 4 – 1 1 ; ▁Jacques ▁Christ ophe ▁Le ▁Bl on ▁( Le ▁Bl ond ), ▁painter , ▁eng ra ver ▁and ▁printer , ▁ 1 7 3 4 – 5 ; ▁Sir ▁William ▁Wol se ley , ▁of ▁Wol se ley , ▁Staff ord shire , ▁fifth ▁baron et , ▁ 1 7 5 7 – ▁ 1 7 6 8 ; ▁Vice - Ad mir al ▁John ▁Campbell , ▁ 1 7 7 4 – 8