Okay, obviously he can't have passed away 1800 - I can see on freebmd:
Percy Augustus L. Machray, m. possibly Mary Jane Broomhead, Sep 1881 quarter, Volume 8c page 982, Chorlton district.
Do you have this marriage certificate? That would give you his father's name and occupation.
(death is there too, in 1900).
I also see on 1881 a family in Chorlton under the name MACKRAY, which includes "Alick" (33), b. Manchester, his wife Sophia, his daughter Jane, and his brother Percy, 24, b. Manchester.
On freebmd.rootsweb.com there's a Percy Augustus Mackray, b. 1857 June quarter, Chorlton, 8c/538.
I'm having trouble finding him or his brother on the 1861 or 1871 censuses.
I think his brother might be Alexander Hutchinson Machray, married Dec 1871 in Manchester district to Sophia Hinchliff.