Hi Telfordmoz
Thanks for getting in touch and I will give as much help as I possibly can.
Most of the records for WW1 soldiers were lost during a bombing raid on London in 1940 when the building they were in was hit and caught fire, most of the damage was actually water damage from the efforts to extinguish the flames. I note that you have his card so I guess you have checked everything on Ancestry.co.uk .
The card records that he received a 1915 Star, this means that he entered the European Theatre of war in that year. The next step is to go to the Great War Forum at
http://1914-1918.invisionzone.com/forums/index.php?act=idx sign up (Free) go to 'Soldiers' and post the question about his possible joining date and give his service number and name, there are experts there who will be able to gice a rough indication i.e. November 1914 etc.
There is a possibility that he fought at the Battle of Bellewaarde 16th June 1915 and if that is the case check out my website Bellewaarde 1915
www.bellewaarde1915.co.uk which will give you a very good understanding of what Arthur went through.
I will check my records and see if I can find details of his death and I will get back to you. You can also keep in touch through Facebook at Bellewaarde 1915 WW1 Group
https://www.facebook.com/#!/groups/Bellewaarde1915/ If this link takes you to my main page click on 'Add Friend' and I'll add you to the group. Speak soon