Newcastle Daily Chronicle 15/02/1916 reports:

(Note differences in spelling of name and his age).
“Officer’s death near Cramlington.
Secretary to the Cleveland Hunt.
Second-Lieutenant Hugh Mosman, 4th Yorkshire Regiment, met with a tragic death on Saturday.
It appears that the deceased was exercising his horse, and going down Crow Hall Lane, near Cramlington, he observed a motor rolley approaching him. As his horse was a frisky one, and thinking it might take fright, he went into a field near Crow Hall Farm. Shortly afterwards the horse was observed coming down the field without its rider. Nurse Bodger, of Cramlington Hall, was passing at the time, and went in search of the officer and found him almost dead. Dr. Phillips was sent for, but by the time he arrived Mosman was dead. The deceased was 54 years of age, and belonged to Ormesby, near Middlesbrough. He was estate agent to Colonel Wharton, and was a keen sportsman, and officiated as secretary to the Cleveland Hunt.

Yesterday an inquest was held at Cramlington by Coroner Rutherford on the body of Hugh Mossman, 55, a second lieutenant in the Yorkshire Regiment.

James Day, 14 years of age, stated that about 2o’clock on Saturday afternoon he was standing at the Crow Hall Road End, when he saw deceased on a horse. Deceased was riding along the inside of the hedge when he fell. The horse ran away.

Miss Bodger, who happened to be in the immediate neighbourhood, stated that she found deceased unconscious but breathing. He died in about ten minutes without speaking.

Dr. Phillip, of the R.A.M.C., who examined the body, said he found no injury whatever, and in his opinion the deceased died from a sudden attack of syncope.

The jury returned a verdict to that effect.”

Yorkshire Regiment entry on 2nd Lieutenant Mosman
The CWGC entry for 2nd Lieutenant Mosman