The discriminant, whose vanishing is the condition that f may possess two equal roots, has the expression j 2 - 6 i 3; it is nine times the discriminant of the cubic resolvent k 3 - 2 ik- 3j, and has also the expression 4(1, t') 6 .

First, there is timber, such as gates, stiles and rails; the first two are, nine times out of ten, awkward jumps, as the take off is either poached by cattle, or else is on the ascent or descent.