As noted earlier John had joined at the end of 1840 and then served in China for over 2 years in the First Opium War (being the first Anglo-Chinese War) between 1840-1842.

If you want to brush up on your history on the Opium Wars then do so here. 

The various battles that they fought in China are listed in the Regimental history as 5^th July 1840 in Tinghai, January 7^th 1841 Bogue Forts, 26th August 1841 at Amoy, 29^th September 1841 in Tinhai (again), later in Chusan, 10^th October 1841 at Chinhai, 13^th October 1841 at Ningpo, then Nankin and in 1842 at Chiang Kiang Foo .  

We find out later that at the storming and capture of Ching Kiang Foon on the 21^st July 1842 John distinguished himself and was severely wounded and for which service he received a medal. 

The regiment returned to Britain. 

In 1844 the regiment having returned home was based in London and then in 1846 in Ireland. If your knowledge of history is better than mine you will know that Great Potato Famine happened between 1840 and 1845, when a million Irish died from hunger and a million immigrated mostly to the USA. There was also a minor rebellion in 1845 when the English sent more troops to Ireland. 

By 1851 the Regiment were in Gibraltar. 

 In England, Ireland and Gibraltar John got into lots of trouble as you can see from the record of his crimes and punishments in the Regiments Defaulters Book. This included 24 hours in the ‘Black Hole’. Also he was subject to a Court Martial in Dublin on 12^th November 1849 as described in the attachment. 

Eventually he left the army and I have a copy of the Proceedings of the Regimental Board held on 29^th November 1853 in Gibraltar. The details of this can be found here but in summary John was discharged following his conduct in Gibraltar. As can be seen however he was not actually discharged until 3^rd July 1854 and Medical Certificates show he had Chronic Rheumatism and Cardiac Disease. He was also found to have had a musket ball in his right shoulder that had to be extracted.