May be a little off topic to the re-entry

. It relates to the same stamp on cover, with the letter still in good condition for someone who may be interested in doing research on early correspondence.
1916
2cT1c Red KGVI Admiral posted from
MILLBROOK.ONT on
MAR 9 1916 to
Miss Linda Hall,17 Fleming Place, Peterboro, Ontario.





With this postal history, I picked up some geographical knowledge about these two Canadian towns.
The Township of Cavan and the Village of
Millbrook, previously part of Durham County, in 1974 became part of Peterborough County, and were amalgamated, along with North Monaghan, into one township — Cavan-Millbrook-North Monaghan in 1998.
The original townships of Cavan and Monaghan were surveyed by John Deyell in 1817, and were named after County Cavan and County Monaghan in Ireland, from which many of its settlers had emigrated. By 1819, there were 244 settlers, and by 1861 the population had risen to 4,901, many of whom were descendants of United Empire Loyalists, veterans of the War of 1812 who had been granted land there, or the original and later settlers from Ireland. After Confederation in 1867, the population began to drop as many families left for Western Canada. The original Irish settlers were Protestants, and many of them were associated with the Orange Order. In the mid-19th century the "Cavan Blazers" were established as a fiercely Protestant vigilante group, who often burned down the farms of Catholic settlers.
Peterborough is a city on the Otonabee River in Central Ontario, Canada. Peterborough is known as the gateway to the Kawarthas, "cottage country", a large recreational region of the province. Peterborough's nickname in the distant past was "The Electric City" as it was the first town in Canada to use electric streetlights. It also underscores the historical and present-day importance of technology and manufacturing as an economic base of the city, which has operations from large multi-national companies such as Siemens, Rolls-Royce Limited, and General Electric, and more local businesses such as Merit Precision Ltd., Dynacast and Bryston. Peterborough is among the best places to retire in Ontario according to some studies, which listed cultural activities and affordable living as some of the factors that attract seniors.