The Austrian Government as a result established shortly afterwards an extensive factory at Weinerisch-Neustadt for the manufacture of war rockets.
Much work and ingenuity was expended about this time in seeking to eliminate the necessity of the rocket stick. Congreve is credited with introducing fins similar in action to the feathers on an arrow; this, however, had been done nearly one hundred years previously, and Frézier illustrates the method in his treatise.
A Mr. Heath, of Boston, is credited with having reached a range of two and a half-miles with a five-pound rocket of this type.
Garnier in 1813 proposed to avoid the alteration in position of the centre of gravity by using a wire or chain with a weight at the end fastened to the centre of the rocket and hanging vertically. From Ruggieri's book it would appear that this idea had often been tried previously.
However, the most successful series of inventions were those based on the principle of the rifle, that to give the rocket a rotary motion in its passage through the air.
In 1815 successful trials were made in America with rockets of the rotary type, rotation being imparted by means of holes bored through the case into the composition in an oblique direction.
Congreve established a factory at Bow for the manufacture of rockets for the East India Company, and Captain Parlby, of the Bengal Artillery, manufactured similar rockets, both being made to rotate, probably on similar lines to the American model. The "Calcutta Journal" of the period contains a discussion of the rival merits of Congreve's and Parlby's rockets.
Hale patented a rocket constructed on similar lines as late as 1844, the holes at the side of the case being nearly tangential. He also gave his name to a service rocket—Hale's
