Bill worked in a shop and as a gardener before joining the Royal Army Medical Corps in 1913 as a stretcher bearer. Promoted to sergeant, he served with the No 1 Cavalry Field Ambulance on the western front from 1915 to 1918.
Sergeant Collins was caught up in a defensive action at the town of Le Hamel.
Casualties were streaming onto my post. Captain Swan, the medical officer, was as busy as he could be dressing casualties. While having a breather, I went to a bank next to this Lewis gunner – he was firing – and I was sat with my back to the bank and my head back. I’d got my tin hat on, having a rest you see. A shell came and I was blown unconscious. How long I was unconscious I don’t know. When I came to I was half woozy, off my head. My tin hat had been forced down on my head, I was badly concussed, and I was wounded round the back of the neck and over the shoulder. My coat was all torn ragged by the bits of shell.
All of a sudden, a stream of machine gun bullets came by. I’ve never heard a more horrifying sound in my life. It was like a thousand gas taps turned on: Psssst! Hssst! Hssst! Hsst! Psssst! magnified a hundred times going hissing past! I had sufficient consciousness to go down – I was flat on my face – instinct! Eventually I found myself back with the field ambulance. I was very shocked, there’s no doubt about that. I still couldn’t tell you exactly what I did to this day. I couldn’t bear to hear a sound; couldn’t bear to hear a pin drop! Every explosion, my heart jumped out of my skin. Over the next three weeks I lost nearly all my hair.