An instant bestseller in 1859, few books have had such a revolutionary impact and left such a lasting impression as On the Origin of Species. Possibly the most important and challenging scientific book ever published, Darwin's language remains surprisingly modern and direct and is presented here in a faithful facsimile edition. The text is taken from the second edition (1860), which is the same as the first except for some minor corrections and so is the purest distillation of Darwin's original vision. It includes a new foreword by David Williams, Researcher at the Natural History Museum,and the introductory appendix, An Historical Sketch of the Recent Progress of Opinion on the Origin, which first appeared in the third edition (1861). As such it is an ideal scholarly resource as well an attractive and excellent value edition for the general reader.