Birthplace:
- Delvine, Dunkeld, Scotland

Birthdate:
- 6 July 1840

Nationality:
- Scottish

Family Background:
- Mackenzie's father was Sir Alexander Muir-Mackenzie, 2nd Baronet, of Delvine

At Sandhurst:
- No

Career before Halifax: 
- Ensign, 12 February 1858 (by purchase)
- Lieutenant, 2 April 1861 (by purchase)
- Captain, 2 February 1864 (by purchase)

Medals & Awards:
- None

Postings while in NS Command:
- Halifax, 11 May 1869 to 24 July 1869

Died:
- 25 June 1909

Muir-Mackenzie was the only titled officer to serve with the 78th in Halifax.  Born on 6 July 1840, and educated at Harrow, he succeeded his father as 3rd Baronet in 1855, and thereby came into possession of the Delvine estate at Dunkeld, in Perthshire. According to the so-called 'New Doomsday' survey of British landowners of 1873, Delvine consisted of 4241 acres, and had an annual income of £6 419. 36.  This would have placed Muir-Mackenzie amongst his nation's very top income earners.  Of 10 000 000 persons with an independent income surveyed in 1867, only 7 500, or .075 per cent, had incomes of over £5 000, and only 49 000 or 0.49 per cent of over £1 000 a year.  Of course, amongst the upper 7 500 there was a great range, with some disposing of much larger sum - the Dukes of Bedford, Bridgewater, Devonshire, and Northumberland, for instance, were worth up to £50 000 a year.  Still, Muir-Mackenzie's £6 149 a year would have constituted a respectable upper level income. £1 000  a year was the sum thought necessary to fully support the life of a 'gentleman'. 

Like Captain Savory, Muir-Mackenzie was with the 78th in Halifax only briefly. He returned home sometime in late June or early July 1869, and on 21 July 1869 sold out of the service. The purchaser of his commission was Lieutenant Henry Frederick Rowley.
After returning to civilian life, in February 1871 Muir-Mackenzie married Francis Rose, daughter of Sir Thomas Moncrieff Bart. Later (1887-92) he served as a major with the Black Watch, and died, without an heir, on 25 June 1909.