APPLES 



161 



The only difficulty met in this combi- objection can be avoided by substituting 



nation plan is due to the fact that the for the equilateral triangle a slightly dif- 



continuous alleys are reduced in width ferent figure. In the upper apex of the 



as they cross the triangular planting, triangle is considered the center of a 



for the obvious reason that the altitude circle and a system of arcs are inscribed 



of a triangle is less than its sides. This about this point which subtend an angle 







® 



Plate I. 



