Born in Poland, Victoria and a Clerk by occupation, Jack Cross was 23 years and single when enlisted on the 29th of May 1917 in the 13th General (Victorian) Reinforcements, Australian Imperial Force, with the rank of Private, Number 61837 Unit embarked from Melbourne, Victoria, on board SS 'Zealandic' on the 5th of October 1918. On the 5th of October 1918 to be VO Sergeant; Reverts to ranks of Private on the 1st of November 1918; On the 12th of November 1918 re-appointed VO Sergeant. On the 5th of February 1919 discharged from Hospital to Sutton Veny. On the 12th of January 1919 admitted to the 3rd New Zealand Hospital Acute Bronchitis. Returned to Australia per 'Medic'- Bronchitis - on the 10th of April 1919. Disembarked on the 31st of May 1919 and Discharged on the 14th of June 1919 with the Termination of Period of Enlistment. Tree No. 3487