The Army & Navy Gazette is currently being loaded onto the British Newspaper Archive and so far they have loaded the years 1860-66 and 1869-71 and I expect more years will soon appear online. I did a quick check and found many such as the following which relates to the formation of the 1st Hertfordshire Battalion.
|Army & Navy Gazette, 4th August, 1860|
Unfortunately the machine transcription left a lot to be desired - and errors in the above example meant that it would not have been found in searches for the place names Ashridge, Hemel, Hempstead, Tring and Watford or for the surnames Dorrien, Cust, and Pearce. Unfortunately such errors occur in all automatically scanned newspaper archives and you have to use your imagination when searching and try alternative search names.
However the accuracy of the surnames and places in the following item relating to the double marriage of the daughters of the late Mr John Beale, of Cheshunt, was satisfactory.
|Army & Navy Gazette, 4th November 1869|