▁ 1 8 6 4 . ▁ ▁She ▁could ▁write ▁v ivid ly ▁and ▁with ▁a ▁dry ▁wit , ▁as ▁when ▁describing ▁the ▁un fortun ate ▁marriage ▁of ▁John ▁Hart ston ge , ▁ ▁Bishop ▁of ▁Der ry , ▁to ▁Isabel le ▁Dan vers , ▁a ▁lady ▁of ▁the ▁Royal ▁Bed ch am ber . ▁ ▁Lord ▁Cow per ▁died ▁after ▁a ▁short ▁ill ness ▁on ▁ 1 0 ▁October ▁ 1 7 2 3 ▁at ▁his ▁residence , ▁Col ne ▁Green , ▁in ▁H ert ford , ▁built ▁by ▁himself ▁in ▁ 1 7 0 4 ▁( dem ol ished ▁by ▁the ▁ 5 th ▁Earl ▁in ▁ 1 8 0 1 ▁on ▁advice ▁from ▁the ▁landscape ▁designer ▁Re pton ) ▁nearby ▁to ▁which ▁the ▁later ▁m ansion ▁of ▁P ans h anger ▁was ▁built ▁in ▁ 1 8 4 0 ▁and ▁also ▁demol ished ▁in ▁ 1 9 5 4 . ▁Mary ▁died ▁gr ief - str icken ▁several ▁months ▁later . ▁The ▁ 1 st ▁Earl ▁and ▁Mary ▁left ▁two ▁sons ▁and ▁two ▁daughters ; ▁their ▁younger ▁son , ▁Sp encer , ▁became ▁Dean ▁of ▁Dur ham . ▁ ▁Mary ▁was ▁the ▁great ▁a unt ▁( by ▁marriage ) ▁of ▁William ▁Cow per , ▁the ▁poet . ▁ ▁S ources ▁ ▁Bo yle , ▁Mary ▁Louis a . ▁Bi ographical ▁catalog ue ▁of ▁the ▁port ra its ▁at ▁P ans h anger , ▁the ▁seat ▁of ▁Earl ▁Cow per . ▁London , ▁Elli ot ▁Stock , ▁ 1 8 8