brownline
n.
A photographic process using light-sensitive iron salts producing brown lines on a neutral background, commonly used to reproduce architectural drawings.
A print with brown lines on a neutral background.
Notes
'Brownline' and 'brownprint' are frequently used synonymously to refer to the same process. A negative is made of a drawing, producing a brownprint; the brownprint is then reprinted to make a positive (brownline). A variety of other processes have been used to make prints described as brownlines and brownprints, although the Vandyke process is one the earliest. Manufactured since the 1890s, this process was frequently found on medium or lightweight paper as the print was often used as an intermediary to create negatives or positives of damaged original drawings.
