Carte-de-Visite, studio Maull & Co. in London

Colonel Phillpotts, Royal Horse Artillery

He was promoted to First Lieutenant on January 10th 1837.
A.T. Phillpotts received the Syrian Medal of 1841 - and must therefore have taken some part in the operations of 1840-41, when the Powers (but France) intervened on behalf of the Ottomans to have the Egyptians evacuate Syria, culminating on the storming of Saint-Jean d'Acre fortress in November 1840.
On November 12th, 1841, he was appointed to Major Wood's Company, 8th Battalion.

On April 29th, 1845, at Woolwich, he was in command of a detachment of the Royal Horse Artillery in charge of keeping "a sufficient open space for the passage" at the parade-ground for the funeral party of Sir George Hoste, C.B..
He was promoted to Second Captain on September 3rd, 1845, and gazetted a Captain on March 11th, 1850 (dated March 6th).
On July 13th 1850, The Times published a list of appointments in the Royal Artillery, stating the following transfer of an officer :
"Second Lieutenant Kelly, from Captain Wodehouse's company, 10th battalion, to Captain Philpotts's (sic) company, 9th battalion".
The 1852 Army List (corrected to 31st December 1851) states that Captain Phillpotts is stil attached to the 9th battalion by then.
The Times precises on August 2nd, 1852 :
"The following companies have been placed under orders to hold themselves in readiness to embark for service at foreign stations :-
(...)
Captain C.L. Fitzgerald's company, 5th battalion, second on the roster, for Gibraltar to relieve Captain Phillpott's (sic) company, 9th battalion, serving at that station since September, 1846." 
Captain Fitzgerald's Company would reach Gibraltar on September 13th.

The Times published on April 15th, 1853 :
"Captain Phillpott's (sic) Company, 9th Battalion, is placed under orders to proceed to Portsmouth, on Monday, the 18th inst., to relieve Captain Levinge's Company, 11th Battalion, and the latter will join head-quarters on the same day."

The West Briton and Cornwall Advertiser published on Friday October 7th, 1853 : Birth, "at Southsea, Portsmouth, on Sunday last, the wife of Captain Phillpotts, Royal Artillery, a son" (Arthur Henry Croker Phillpotts, later a Royal Horse Artillery officer himself).

On June 5th, 1854, The Times announced :
"The Lieutenant-General of the Ordnance has appointed Captain A.T.Phillpotts to the command of Troop A of the Royal Horse Artillery, vice Captain Taylor, promoted to be Lieutenant-Colonel". 

On July 3rd 1854, his troop of Royal Horse Artillery was in attendance at the departure of the King of Portugal, at Woolwich dockyard, firing a Royal salute on his boarding the Royal steam yacht Mindelo. On May 19th 1855, half a troop of RHA, under his command, took part in a review on the Common, and "precisely at 12 o'clock a Royal salute of 21 guns was fired". 
He would soon have the opportunity to use his guns in a different way in the Crimea. 

The Times published on June 2nd, 1855 :
"The Peninsular and Oriental Company's screw steamship Simla transport No.118, Captain T.S.Russell, will embark at Southampton, this day the A troop of Royal Artillery for conveyance to the Crimea, consisting of 300 horses and 350 men, under the command of Captain Philpott (sic)".

A precision was made on June 4th :
"The embarcation of the A troop of Royal Horse, under the command of Captain Philpotts (sic), took place (as stated in The Times of Saturday) at Southampton on that day on board the Peninsular and Oriental Company's screw steamship Simla, transport No.118, Captain Russell. The numbers previously stated include a detachment of Captain Travers' company of Royal Artillery, consisting of 50 men and horses. The embarcation, which was under the sole superintendence of Captain Engledue, superintendent of the Peninsular and Oriental Company at Southampton, was most admirably arranged, and was in every respect as perfect as could possibly be. The whole of the horses, men, and appointments were on board, and the gangways removed from the side of the ship, by 3 p.m., although it was not until the morning of Saturday that the animals and troops arrived at that port. Captain Dacres, R.N., Admiralty Superintendent at Southampton, was present and rendered essential service. The Simla was moored in the inner dock, the waters of which always retain a regular heigth, which is highly advantageous in the embarkation of horses, enabling the animals to be easily walked on board. The men appeared in excellent spirits, and the horses are all of a first-class character. The Simla has been victualled for 400 men for six months by Messrs. Cooksey, merchants, of Southampton. She left for the Crimea yesterday at noon."   

The Times published on June 19th, 1855 a Malta letter of the 13th inst., stating :
" (...) Shortly afterwards, the screw steam transport simla (118), belonging to the Peninsular and Oriental Company, came in from Southampton with the following :- (...) For Balaklava, Captains Phillpotts, Jones, Mercer, and Dynaly ; Lieutenants Brackenburgh, Gore, W.Booth, Pill, and L'Estrange ; Surgeons Clifford and Brennan, 276 men and 289 horses of the Royal Horse Artillery ; (...) "

Arthur Thomas Phillpotts was promoted to Lieutenant-Colonel, dated August 13th, 1855, receiving a Brevet of Colonel on the same day. He served at the siege and fall of Sebastopol (Medal with Clasp, 5th Class of the Medjidie, and Turkish Medal).

In September 1856, he was at Woolwich, in command of P Battery (Field Artillery), during the annual inspection of the Royal Artillery.
In July 1857, he was to proceed to India, to be in command of the force of Royal Artillery to be stationed in the Bombay district. 
The Bombay Times listed him on April 19th 1858, as resident at Mahableshwur.
No war service is recorded for the Mutiny.

On March 1859, The Times reported :
"Colonel Phillpotts, Royal Horse Artillery, has arrived at head-quarters, Woolwich, from Bombay, in order to assume the duties of his appointment in command of the brigade of Royal Horse Artillery at Woolwich, in succession to Colonel Maude, appointed to the constabulary force in Dublin."

In October 1860, he was at Aldershott, in command of the Horse Brigade of the Royal Artillery.
On March 18th, 1861, he was transferred from Aldershott to Dublin, "to command the Royal Horse Artillery in Ireland".
The Cork Examiner published on September 3rd, 1862 : Births, "at Portobello, Dublin, the wife of Col. Phillpotts, Royal Horse Artillery, of a son"
He was still holding that position on February 20th, 1864.

He was gazettes a Colonel on January 13th, 1865 (dated December 15th 1864). He commanded B Brigade, Royal Horse Artillery (the "1st Horse Brigade" had been divided in two Brigades, named "A" and "B", in April 1864).
He was promoted to Major-General in 1873. By December 1877 he was a Lieutenant-General and held the appointment of Inspector-General of Artillery.
He vacated that appointment on September 1st, 1880, and was gazetted a Colonel Commandant of the Royal Regiment of Artillery on December 14th 1880 (dated November 26th).
He was placed on the Retired List with the honorary rank of General on May 23rd, 1882.
He died in the midst of the year 1890.

The photograph shows him as a Colonel in the Royal Horse Artillery.
It very likely dates from 1873.