Caliber Weight Type of Projectile Elevation Range Smoothbore of gun projectile weight of same (pounds) (pounds) caliber 10-pounder 890 Shell 9.75 5 deg. 2,000 3-pounder. do 9.75 20 deg. 5,000 20-pounder 1,750 do 18.75 5 deg. 2,100 6-pounder. do 18.75 15 deg. 4,400 30-pounder 4,200 do 29.00 15 deg. 4,800 9-pounder. do 29.00 25 deg. 6,700 Long shell 101.00 15 deg. 4,790 do 101.00 25 deg. 6,820 Hollow shot 80.00 25 deg. 7,180 do 80.00 35 deg. 8,453 Amazingly enough, these ranges were obtained with about the same amount of powder used for the smoothbores of similar caliber: the 10-pounder Parrott used only a pound of powder; the 20-pounder used a two-pound charge; and the 30-pounder, 3-1/4 pounds! HOWITZERS The howitzer was invented by the Dutch in the seventeenth century to throw larger projectiles (usually bombs) than could the field pieces, in a high trajectory similar to the mortar, but from a lighter and more mobile weapon. The wide-purpose efficiency of the howitzer was appreciated almost at once, and it was soon adopted by all European armies. The weapon owed its mobility to a rugged, two-wheeled carriage like a field carriage, but with a relatively short trail that permitted the wide arc of elevation needed for this weapon. [Illustration: Figure 34--SPANISH 6-INCH HOWITZER (1759-88). This bronze piece was founded during the reign of Charles III and bears his shield. a--Dolphin, or handle, b--Bore, c--Powder chamber.] English howitzers of the 1750's were of three calibers: 5.8-, 8-, and 10-inch, but the 10-incher was so heavy (some 50 inches long and over 3,500 pounds) that it was quickly discarded. Mueller deplored the superfluous weight of these pieces and developed 6-, 8-, 10, and 13-inch howitzers in which, by a more calculated distribution of the metal, he achieved much lighter weapons. Mueller's howitzers survived in the early 6- to 10-inch pieces of United States artillery and one fine little 24-pounder of the late eighteenth century happens to be among the armament of Castillo de San Marcos, along with some early nineteenth century howitzers. The British, incidentally, were the first to bring this type gun to Florida. None appeared on the Castillo inventory until the 1760's. [Illustration: Figure 35--ENGLISH 8-INCH "HOWITZ" CARRIAGE (1756). The short trail enabled greater latitude in elevating the howitzer.]