Picked this up recently.

Dated September 21 1910 it is an official cover from the Patent Office in Ottawa, sporting an Ottawa Canada FREE cancel and a hand stamped signature.
The black border mourns the passing of King Edward VII the previous May 6.
Two questions.
1. Does anyone recognize, or can read the signature. No joy on google.
2. Does anyone know how long the Canadian Government would have used such mourning covers after the passing of a Monarch? Again, google is no help on this one.