Crop rotation British Agricultural Revolution. The rotation between arable and ley is sometimes called ley farming. George Washington Carver (1860s–1943) studied crop-rotation methods in the United States, teaching southern farmers to rotate soil-depleting crops like cotton with soil-enriching crops like peanuts and peas. In the Green Revolution of the mid-20th century the traditional practice of crop rotation gave way in some parts of the world to the practice of supplementing the chemical inputs to the soil through topdressing with fertilizers, adding (for example) ammonium nitrate or urea and restoring soil pH with lime. Such practices aimed to increase yields, to prepare soil
Drinking fountain contaminated with lead. This is especially common in older buildings with obsolete plumbing. In the 1970s, this fear of contamination in tap water was hyped by producers of bottled water, thereby changing attitudes to publicly provided water in drinking fountains, which began to disappear from city streets. The term "bubbler" is used in some regional dialects of the United States and in Australia. A survey of US dialects undertaken between 2002 and 2004 found the word "bubbler" is commonly used in southern and eastern Wisconsin and in Massachusetts and Rhode Island. The phrase "drinking fountain" was common in the rest