 During late 1777 he helped raise the 72nd Regiment of Foot (Royal Manchester Volunteers) and served with that regiment at the Great Siege of Gibraltar, being appointed assistant Engineer there by Governor George Eliott in 1779.In 1781, he joined Colonel James Francis Erskine in trying to raise a battalion of Swiss Chasseurs for service with the East India Company.The venture was stopped by the Swiss authorities with Augustus and fellow officers being jailed for several months.