493,588. Plotting-scales. AMARASEKERA, G. M. P. Jan. 7, 1938, No. 572. Convention date, Jan. 7, 1937. [Class 97 (iii)] A cursor 18 slides between straight edges 11 which are spaced apart by end pieces 12, scales are provided on a straight edge 11 and on an edge of the cursor 18 perpendicular to the straight edge 11, and a pointer 17 is provided on an end piece 12 with its tip at the intersection of the perpendiculars through the zeros on the two scales. Scales may be provided on both straight edges and pointers 17 on both end pieces 12. The instrument facilitates plotting points offset from a base line. Specificaton 19216/91, [Class 97], is' referred to.