Named on the Netherthong war memorial, Netherthong being a small village near Holmfirth, south of Huddersfield. Although he appears on the memorial as J. Walker, the online History of Netherthong gives his first name as James.
The Netherthong website has a small section on the ABW, but no mention of James Walker. So far, I've been through the Holmfirth Express newspaper, from 6th January to 5th May 1900, and not found a mention of him, so I assume he must have been a regular soldier, or possibly a reservist.
I tried to find his birth registration; in the late 1800s Netherthong and Holmfirth were in the Huddersfield Registration District, and I could find only one possible -- James Edward Walker, birth registered in the June Quarter of 1863, whose mother's maiden name was Gledhill, which, if that was the Netherthong man, would have him in his late 30s when he died.
There's a Gledhill named on the Netherthong memorial, and the village history site has this on him - "George Richard Gledhill, 2nd. LT. 1/5 Battalion, Duke of Wellington;s regiment. He was a family member of the firm Walter Gledhill & Sons, Bridge Mills."
So, possibly, he was James Edward Walker, born in 1863.