From the Bootle Times:
BOOTLE FAMILY'S LOSS.
CAPTAIN ALEC MACK KILLED IN ACTION.
A well-known and highly esteemed Bootle family has suffered a bereavement through the death in action of Captain Isaac Alexander (Alec) Mack. The young officer was the third son of Alderman Isaac A. Mack, J.P., and of Mrs. Mack, of "Manhattan," 44, Balliol-road, Captain Mack, who was a capable athlete, and esteemed in cricketing circles, was only twenty-four years of age. Educated at Leys and Jesus College, Cambridge, where he had taken the B.A. with honours, he went straight from the university to join the Army. Eventually he was attached to the trench mortar battery of the Suffolk Regiment, and recently he was promoted captain. He had been in France for some time, and had seen a good deal of fighting. His death took place while leading his men in the desperate fighting on July 1st. Much sympathy will be felt for his parents in their great loss. Mr. and Mrs. Mack have two other sons in the Army - Lieut. Lovel Mack, who is abroad with the East Lancashire Regiment, and Lieut. Arthur Mack, Royal Lancaster Regiment. who, after an attack of enteric fever, was put on home service.
Universal sympathy has been expressed for the family in heir terrible bereavement.
Bootle Times 21st July 1916
Thanks to Julia Margretts for the photograph.