“ The central idea of his teaching was that naval supremacy is the condition precedent of all vigorous military offensive across the seas, and, conversely, that no vigorous military offensive can be undertaken across the seas until the naval force of the enemy has been accounted for—either destroyed or defeated and compelled to withdraw to the shelter of its own ports, or at least driven from the seas by the menace of a force it dare not encounter in the open. ”

“ He did not invent the term “sea-power,”—it is, as is shown elsewhere (see Sea-Power) , of very ancient origin,—nor did he employ it until Captain Mahan had made it a household word with all. But he thoroughly grasped its conditions, and in his great work on naval warfare (first published in 1891) he enunciated its principles with great cogency and with keen historic insight. ”

“ Next year he was appointed captain of the steam reserve at Portsmouth; and after serving three years in that capacity, he remained at Portsmouth as flag-captain to the commander-in-chief until 1886, when he was retired by superannuation before he had attained flag rank. Subsequently he became rear-admiral, and finally vice-admiral on the retired list.
Few men of his day had seen more active and more varied service than Colomb. ”