13+ Health Benefits of Apple Cider Vinegar. 1  Your Brain on Trust: Why Weâre Hardwired to Rely On Others. 2  19 Easy Ways You Can Torch 200 Calories In a Blink of an Eye. 3  This Mom Lost Over 150 Pounds by Cutting Out 4 Foods.
O. volvulus is transmitted by sandflies, and their role in the transmission of onchocerciasis was discovered by the Scottish parasitologist Breadablane Blacklock in Sierra Leone in the mid-1920s (19). There are accounts of the history of onchocerciasis by Grove (105) and Muller (192).
The modern era of anesthesia began in the late eighteenth century when chemists began to investigate the use of various gases. Joseph Priestley (1733-1804) discovered nitrous oxide in 1772, and in 1800 Humphry Davy (1778-1829) discovered that the gas had anesthetic properties when it was inhaled.