154 
Dr Taylor, Geometrical Notes on Theorems 
But In/pn = AM/QM = QM/4>a. 
Therefore PN. In = AI. QM. 
In what follows Q is to be taken as in the figure and so that 
the algebraic sum of PN, pn, QM is zero. 
3. Let the normals PG, pg produced meet in a point H whose 
ordinate is UK, and on AK produced take KJ equal to AL 
Then JH will be the normal at Q. 
For Ini IN = pn/PN = KG /Kg, 
the subnormals being each equal to 2 a. 
