The list of 10th Hussars men who had become prisoners of war by December 1914 is tiny. It took the form of a two-page letter typed by Mrs E Mackenzie of the Tenth (PWO) Hussars Association and was sent to Sir Ernest Goodhart on the 19th December 1918. At the time of writing, at least six of the men were still being held in German camps.
At first glance, Corporal Addison looks to be the longest serving man here, assuming that is that the other men's numbers all belong to the regimental number series issued to the Corps of Hussars from 1907. That would place Corporal Addison as a 1907 enlistment, and all the other men a couple of years behind him, enlisting in 1909 and 1910.
On the other hand though - and this is where you need to be careful with line cavalry numbering - the numbers issued to all of the men except Corporal Addison could, in theory, have been issued to the 10th Hussars before 1907. This would make 4238 Sergeant Hawkes the longest serving man (enlisted 1899), with the other men enlisting between 1900 and 1906).
In actual fact, Lance-Corporal Arthur H Hawkes does indeed appear on medal rolls for the Queen's South Africa Medal and King's South Africa Medal and so he is the longest serving man in the list below.
909 Corporal Alfred H Addison
4686 Private George R Bird
6545 Private P Cairns
5568 Private Joseph Cassidy
5559 Private Arthur G Cater
5590 Private H Grant
4238 Sergeant H Hawkes
5759 Corporal William R Miller
5422 Private E Reeve
For more information on cavalry numbering and that crucial change from regimental numbering by regiment to regimental numbering by corps, have a look at my post on King's and Queen's Regulations, and in particular Army Order 289 of December 1906 which, for the modern day researcher, really is a vital document that should be pinned up somewhere where it won't be missed. Or alternatively, just bookmark this page.
Pictured above in about 1901, Prince Edward, HRH The Prince of Wales; Later King Edward VII, Colonel of the 10th Hussars.
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