History of geometry History of geometry Geometry (from the ; "geo-" "earth", "-metron" "measurement") arose as the field of knowledge dealing with spatial relationships. Geometry was one of the two fields of pre-modern mathematics, the other being the study of numbers (arithmetic). Classic geometry was focused in compass and straightedge constructions. Geometry was revolutionized by Euclid, who introduced mathematical rigor and the axiomatic method still in use today. His book, "The Elements" is widely considered the most influential textbook of all time, and was known to all educated people in the West until the middle of the 20th century. In modern times, geometric
The Crown of Ptolemy The Crown of Ptolemy The Crown of Ptolemy is the third and last book in the "Percy Jackson and the Olympians" and "The Kane Chronicles" crossover series. It was released in the back of the paperback version of "The House of Hades" on March 31, 2015, and later as an ebook and audiobook. The ebook edition was released May 12, 2015. On January 15, 2015, Rick Riordan announced a third crossover story titled "The Crown of Ptolemy" on his Twitter account. His announcement included the fact that the short story would be first published in the paperback version of "The