Time-Span of Formation, Bonnet & Cie
(inverse of) at some time within
(inverse of) begin of the begin
(inverse of) ongoing throughout
---01
---01
--01
--01
1865
1865
(inverse of) at some time within
(inverse of) begin of the begin
(inverse of) ongoing throughout
---01
---01
--01
--01
1810
1810