London, HMSO, 1871. Folio. Not bound. Two stamps and small paper label and two lines written in contemporary hand to upper part (not affecting text) of front wrapper/Title-page. First and last leaves with heavy browning. 31 pp. (including 4 pp. of coloured plates).
Rare first printing of Major-General John St. George's report on the comparative trials with a 9-pr. M.L. battery of bronze guns, and a battery composed of 12-pr and 9-pr. B.L wrought-iron guns.