Svg files for 1521, 1541 and 1611.

I tried autogenerating svgs for all of the pngs, but that did not work well for most images. Below is the source used:

#!/bin/bash
#Origin: https://gist.github.com/ykarikos/2892009
 
if [ "$1" == "" ]; then
  echo Usage: $0 pngfile
  exit 0;
fi
 
FILE=`basename $1 .png`
 
if [ ! -e $FILE.png ]; then
  echo $FILE.png does not exist
  exit 1;
fi
 
convert $FILE.png $FILE.pnm
potrace -s -o $FILE.svg $FILE.pnm
rm $FILE.pnm