Page:The Development of Navies During the Last Half-Century.djvu/204

 breech was closed by an iron wedge entered from the top of the gun. With the usual interval for improvements, experiments were carried out in Italy with this gun, which showed considerable advance in accuracy over the smooth bores.

Wahrendorff's gun was similar in principle, though the details were different. Trials took place at Shoeburyness in 1850 with both the Wahrendorff and Cavalli gun, but the breech mechanism was defective, and neither was adopted. So matters rested until after the Crimean War, when the question was seriously taken up in this country. Able inventors turned their attention to rifled ordnance, and among the foremost were Messrs Armstrong and Whitworth. In fact Mr Armstrong had made a small rifled gun in 1855, and the principle on which this was constructed was eventually adopted. The first had a steel barrel strengthened externally by wrought-iron, applied in a twisted or spiral form as in a fowling piece. This gives the strength due to the fibre of the material being disposed at right angles to the bore. The gun was rifled with numerous small grooves. The projectiles were cylindrical, of cast-iron, and coated with lead, to take the grooves and so receive rotation. Being pushed in from the rear or breech, allowance for windage was unnecessary, as the projectile was only inserted sufficiently far for the lead coating to abut against the beginning of the rifling, and the action of the powder forced the projectile to take the grooves.

Satisfactory results were obtained, and a larger gun was constructed. The steel barrel was abandoned as