Calculating a wall's declination from south or north using actual and calculated azimuths
use the spreadsheet as an assist (for the PC in Excel) use the spreadsheet on this page as an assist (for the PDA in DocsToGo)
This is a PDF file that discusses measuring a wall's declination from south or north by using actual and computed azimuths, and is an extract from the main book ILLUSTRATING SHADOWS. This is a step by step process, and optionally uses the general spreadsheet to assist.