The naval architect's and shipbuilder's pocket-book of formulae, rules, and tables and marine engineer's and surveyor's handy book of reference (1884)
Mackrow, Clement · London, C. Lockwood and co. · leaf 26
3L To draw a tangent to any jmnfin a parabola. (Fig. 3t).) From the vertex A of the paraboladraw AC perpendicular to AB, andmake it equal to half BD ; throughthe points c and D draw a line, whichwill be the tangent required. GEOMETRY. 17 … \ \I \ \ \ i3 1 \ \ I V \ \i FiQ. 41. 32. :7J describe a Jiijptrhola, the diameter^ abscissa, and double4)rdiiiate being given. (Fig. 40.) Let AB be the diameter, bc itsabscissa, and de its double ordinate ;then through B draw GF paralleland equal to DE; draw also DG andEF parallel to the abscissa…
