Q. I have in a section of my property that faces the lake and there is more than ten tefachim from the edge of the water to the top of the land. This is slanted, as a 'tel hamislaket'. What is the minimum permitted angle for "tel hamislaket"?
A. Tel Hamislaket is a mechitza created by a slope that rises ten tefachim high (aprox. one meter) extending out 24 tefachim (aprox. 2.4 m.). There are two opinions as to how we measure this last length. Mishne Berura (345,5), maintains that this represents the length of the slanted ramp (the hypotenuse, if it is visualized as a right triangle). A second opinion (Macharalbach 19 quoting R"A Zechut) sustains that we measure the length of the adjacent side or the flat ground underneath the slope.
Horav Shlomo Miller Shlit"a maintains that we are to follow the Mishna Berura's view and use the sine value of 10/24 (0.4166) closest to an angle of 25°.
Rabbi A. Bartfeld as
revised by Horav Shlomo Miller Shlit"a
Important Numbers
