A photometric method for quantitative estimation of the area of irregular microscopic objects.

The area of small irregular microscopic objects can be estimated by projecting the image of the objects on to tracing paper, making a tracing using a fibre tipped sketch pen, eluting the ink from the paper, and estimating the colour photometrically. Similarly treated spots of known area are used as standards. The method can also be used to measure the lengths of lines that are too complicated to be measured by other means.