Based on this Tosafot in Bava Metzia 28a (D"H Chamisha Asar Yom), Eretz Israel is a square (400 sq. Parsah), and the distance between Jerusalem and the Jordan river is 1/39th the distance between ...
In high-altitude cities, water boils at a lower temperature than the standard 212 degrees Farenheit. For example, in Denver the boiling point is about 203 degrees. Can one kasher utensils with hagalah ...