Most carpenters frame and trim whole houses with nothing more than a 4- or 6-foot spirit level to find plumb and level. But a level is a poor tool for plumbing tall walls and columns, for laying out long horizontal runs of trim, and for aligning window heads. Mistakes made while framing walls resurface later when you frame the roof; sloppy installation of windows and doors fouls up the alignment of frieze boards and clapboard courses; and small leveling errors accumulate into major installation problems with interior trim and cabinets. In each of these cases, a transit is much more accurate. While it may seem like a lot of extra trouble
