In a magnet stirring apparatus comprising a base which includes a plurality of magnet coils and onto which respective vessels can be placed, said vessels being made of a non-magnetic material and each containing a magnetic stirring bar as well as the liquid to be stirred, the stability of the stirring...http://www.google.com.tw/patents/US4568195?utm_source=gb-gplus-share專利 US4568195 - Magnet stirring apparatus
