The Mystery of the Aztec Warrior have only one clue to work with: the name of a complete stranger who can help find the answers, Roberto Hermosa. Despite the harassments, the threats, and the attacks made upon them by an unknown, sinister gang, Frank and Joe unravel clue after clue in their adventure-packed search for the living descendant of the mighty Aztec nation which once ruled Mexico. The hunt leads to a marketplace in Mexico City, to the Pyramids at Teotihuacan, to the tombs of Oaxaca-where Chet Morton, the Hardy's buddy, is nearly buried alive by foul play. It takes as much high courage as clever
Evolution of timpani in the 18th and 19th centuries Evolution of timpani in the 18th and 19th centuries The modern timpani evolved in the 18th and 19th centuries from the simple 12th-century membranophone of the Naker to a complex instrument, consisting of a suspended kettle with a foot operated clutch, capable of rapid tuning. The technological evolution of the instrument led to increased interest in its capabilities and sound among such composers as Ludwig van Beethoven, Robert Schumann, and Hector Berlioz. Initially used only outdoors, the instrument underwent modifications in the 16th and 17th centuries that led to its incorporation into chamber ensembles. During the 18th and 19th centuries,