During the latter part of the 17th century, the scientific foundations that apply to all modern rocketry were laid by the English scientist Sir Isaac Newton (1642-1727). Newton expressed his understanding of physical motion via three scientific laws. The laws explain how rockets work and why they are able to function in the vacuum of outer space. Newton's laws had a practical impact on the design of rockets. About 1720, a Dutch professor, Willem Gravesande, built model cars propelled by jets of steam. At the same time, rocket experimenters in Germany and Russia began working with rockets of greater and greater mass. Some of these rockets became so powerful that their escaping exhaust flames bored deep holes in the ground even before liftoff.
The Congreve rockets were highly successful in battle. Used by British ships to pound Fort McHenry in the War of 1812, they inspired Francis Scott Key to write about "the rockets' red glare" in his poem, "The Siege of Fort McHenry," which we know today as "The Star-Spangled Banner."
Even with Congreve's work, the accuracy of rockets still had not improved much from the early days. The devastating nature of war rockets during this era was not their accuracy or power, but their numbers. During a typical siege, thousands of them might be fired at the enemy. The effects of such a rain of rockets could be devastating! All over the world, rocket researchers experimented with ways to improve accuracy. The Englishman William Hale developed a technique called spin stabilization, in which the escaping exhaust gases expanded through small vanes at the bottom of the rocket, causing it to spin much as a bullet does in flight. Variations of this principle are still used today.
Rockets continued to be used with success in battles all over the European continent. However, in a war with Prussia, the Austrian rocket brigades met their match against newly designed artillery pieces. Breech-loading cannon with rifled barrels and exploding warheads were far more effective weapons of war than the best rockets. Once again, rockets were relegated to peacetime uses.