In 1872 Siacci was promoted to Professor of Ballistics at the Military Academy and he continued to hold this post until his army career ended in 1892 by which time he had reached the rank of major general.
Sa 1872 Siacci ay itaas na Professor ng Ballistics at ang Military Academy at siya ang patuloy na hawakan ang post na ito hanggang sa kanyang hukbo karera natapos sa 1892 na kung saan ang oras niya naabot ang ranggo ng major general.