1.de PS	\" start picture
2.	\" $1 is height, $2 is width, both in inches
3.if \\$1>0 .sp .35
4.in (\\n(.lu-\\$2)/2u
5.ne \\$1
6..
7.de PE	\" end of picture
8.in
9.if \\$1>0 .sp .65
10..
11