Keywords: Heraldic gurges (whirlpool) Gorges.svg A heraldic whirlpool or gurges shown on a shield This is a version of one coat of arms of the w Gorges family of England Sir Maurice Russell 1356 02 02 “ 1416 06 27 a High Sheriff of Gloucestershire was descended from this family Own ; vector equivalent of the former image en File GorgesArmsMediaevalShield jpg AnonMoos 2011-09-18 Technical details The Archimedean spiral was generated from the following vector PostScript source code <pre> 300 396 translate - 42 42 scale/pi 3 1415926535898 def/R 180 pi div def/W 15 def/U 7 01 def/D 180 def/C 54 pi div def/L /Y 0 def 0 W U 360 mul 7 dup repeat D add cos/H exch def D add sin/G exch def H mul R div/Q exch def G mul R div/E exch def Q C mul/x exch def E C mul/y exch def/S G Q add H E sub div def G 0 gt G 0 eq H -1 eq and or /F -1 def /F 1 def ifelse/A exch def A 49 294 lt A 180 gt A 196 274 lt and or /F F neg def if W sub dup dup dup D add cos C mul mul R div/M exch def D add sin C mul mul R div/N exch def W add dup dup dup D add cos C mul mul R div/O exch def D add sin C mul mul R div/V exch def/P x M sub dup mul y N sub dup mul add sqrt pi div def/Z x O sub dup mul y V sub dup mul add sqrt pi div def/B S S mul 1 add sqrt def 0 eq 0 0 moveto/X D cos Z mul def X Y x 1 F mul B div P mul sub y S F mul B div P mul sub x y curveto /X x 1 F mul B div Z mul add def/Y y S F mul B div Z mul add def ifelse for stroke def L/U 6 51 def/D 0 def L showpage EOF</pre> Maurice Russell Images with PostScript source code Spirals in heraldry SVG coat of arms elements Gorges arms ancient |