Periodic Table s p d f Blocks. Periodic table is divided into four blocks, and elements are placed into these blocks based on the sub-shell in which their last electron enters. This classification divides the elements into four types s-, p-, d- and f- block elements.
It was during this visit that Ansel Adams took his first shot with his new Kodak Brownie Box camera. It highly fascinated him. In 1917, he returned alone to the National Park; this time equipped with a better camera and tripod. The visit intensified his interest in photography.
Ansel Easton Adams was born on February 20, 1902 in San Francisco. He was the only son of Charles Hitchcock Adams and Olive Bray Adams. Initially Charles was involved with running of the lumber trading business established by his father. Later he set up an insurance agency and a chemical factory.