Guido of Arezzo
In the 12th century, a development in teaching and learning music in a more efficient manner had arisen. Guido of Arezzo's alleged development of the Guidonian hand, more than a hundred years after his death, allowed for musicians to label a specific joint or fingertip with the gamut (also referred to as the hexachord in the modern era). Using specific joints of the hand and fingertips transformed the way one would learn and memorize solmization syllables. Not only did the Guidonian hand become a standard use in preparing music in the 12th century, its popularity grew more widespread well into the 17th and 18th century. The knowledge and use of the Guidonian hand would allow a musician to simply transpose, identify intervals, and aid in use of notation and the creation of new music. Musicians were able to sing and memorize longer sections of music and counterpoint during performances and the amount of time spent diminished dramatically.
The Black Hand (book)
Beginning in the summer of 1903, an insidious crime wave filled New York City, and then the entire country, with fear. The children of Italian immigrants were kidnapped, and dozens of innocent victims were gunned down. Bombs tore apart tenement buildings. Judges, senators, Rockefellers, and society matrons were threatened with gruesome deaths. The perpetrators seemed both omnipresent and invisible. Their only calling card: the symbol of a black hand. The crimes whipped up the slavering tabloid press and heated ethnic tensions to the boiling point. Standing between the American public and the Black Hand’s lawlessness was Joseph Petrosino – dubbed the "Italian Sherlock Holmes" he was a famously dogged and ingenious detective, and a master of disguise. As the crimes grew ever more bizarre and the Black Hand's activities spread far beyond New York’s borders, Petrosino and the all-Italian police squad he assembled raced to capture members of the secret criminal society before the country’s anti-immigrant tremors exploded into catastrophe. Petrosino's quest to root out the source of the Black Hand's power would take him all the way to Sicily—but at a terrible cost. Since the book was released, it was received acclaimed by critics. Author Mark Adams said: "The Black Hand is nonfiction noir at its best: a real-life Godfather prequel that pits an unforgettable Italian-American hero against the seemingly unstoppable menace that would become the New York mafia". Kirkus Reviews said it was: "A thrilling tale of the "Italian Sherlock Holmes"".