A dropping of cow dung.
{{quote-text|en|year=1979|title=Annual Review of Energy|isbn=0824323025|author=Jack M. Hollander; Melvin K. Simmons; David O. Wood|url=http://books.google.com/books?vid=ISBN0824323025&id=KMT-OXwsO0YC&q=cowpat+date:0-1980&dq=cowpat+date:0-1980&pgis=1