Roller coaster   In what may be a practical application, NASA
has announced that it will build one to help astronauts escape
the Ares I launch pad in an emergency.       "Russian Mountains"
The oldest roller coasters descended from the so-called Russian
Mountains, which were specially constructed hills of ice,
located especially around Saint Petersburg. Built in the 17th
century, the slides were built to a height of between 70 Some
historians say the first real roller coaster was built under the
orders of Russia's Catherine the Grhe Gardens of Oranienbaum
(today Lomonosov) in Saint Petersburg in the year 1784. Other
historians believe that the first roller coaster was built by
the French. The Les Montagnes Russes à Belleville (The Russian
Mountains of Belleville) constructed in Paris in 1812 and the
Promenades Aériennes both featured wheeled cars securely locked
to the track, guide rails to keep them on course, and higher
speeds.  Scenic gravity railroads  In 1827, a mining company in
Summit Hill, Pennsylvan