Other important places on the Net to visit.

Dan Holohan is a fine writer of magazine articles and books. He says he specializes in hydronic heat, but his writing skills take you beyond such a specialty. He is considered the guru of steam heating by a great many people. Bookmark his site when you get there because you will want to return often for the other stuff.
Dan Holohan's Site
The Math Forum is a special place for us. Part of our book, Math to Build On, is available on-line there. Sarah Seastone did a great job of changing these parts of the book to html for the web.
Hamilton's Math to Build On

Another great feature of the Math Forum is Ask Dr. Math. Students of all ages can go here and ask any kind of math question. I wish this service would have been around when I was growing up.
Ask Dr. Math

The National Building Museum has a fine web site that you ought to see.
National Building Museum

CTP Home Reviews Order Page Pipefitter.com

CTP Address