48 TJte Dalhy Profile Recorder 



5. Use of the Record to plot a Contour Line 

 ON THE Timber Surface. 



The point on the timber surface corresponding to any point on the 

 record can be identified by placing guide frame and stock so that the 

 pencil is brought over the point on the record. The roller will then 

 mark the corresponding point on the timber surface. 



The series of points lying on a contour line on the record can thus 

 be identified on the timber surface and an actual contour line can then 

 be drawn on the timber surface itself. The meaning of such a line is 

 that all points on it are equally distant from the reference plane con- 

 taining the point Z and parallel to the points A, B and C which have 

 been definitely imprinted on the timber surface by the three studs 

 against which the timber sample was clamped. 



