First published in 1939, Clark’s Positioning in Radiography is the preeminent text on positioning technique for diagnostic radiographers. Whilst retaining the clear and easy-to-follow structure of the previous edition, the thirteenth edition includes a number of changes and innovations in radiographic technique. The text has been extensively updated, including a new section on evaluating images, The 10-point plan, which is linked throughout to a listing of Essential image characteristics fo...

Volcanoes are unquestionably one of the most spectacular and awe-inspiring features of the physical world. Our paradoxical fascination with them stems from their majestic beauty and powerful, sometimes deadly, destructiveness. Notwithstanding the tremendous advances in volcanology since ancient times, some of the mystery surrounding volcanic eruptions remains today. The Encyclopedia of Volcanoes summarizes our present knowledge of volcanoes; it provides a comprehensive source of information o...