Scientific American Supplement, No. 492, June 6, 1885

The Spanish Government is now engaged in supplying some of its principal fortifications with heavy guns of the most improved construction. The defenses of Cadiz and Ceuta have been greatly strengthened in this respect. The most recent additions are some very powerful Krupp guns for the fortress of Isabel II. , at Mahon. One of our engravings shows the great revolving crane by which the guns were lifted and placed on the truck for conveyance over a track to their intended position. This crane is worked by eight men, and readily lifts burdens of about 200, 000 lb. The other engraving shows the jack frame and jacks employed to remove the gun from the temporary truck. At a range of 7, 000 yards these guns are able to penetrate iron plates of two feet thickness.