Hello Andy, I have received the Birth Certificate for Joseph Armstrong and it shows his birth to be at 71 Newgate Street, Morpeth which according to the 1911 Census is Morpeth Workhouse. Also the Birth is reported by S Hoey who was Master of the Workhouse again in the same Census. No father's name on the Certificate but the mother was Margaret Jane Armstrong, a Domestic Servant from Ashngton near to Morpeth.
Just need to try and link this birth in with what I have got already but it appears to be the correct person.
Thanks again