48 



measured, the arm assumes a position at right angles to the 

 scale which it touches at the edges (c) and (b). 



Instead of being graduated in the ordinary way, the rule 

 (A A), in calipers intended to be used by illiterate workmen, 

 may, with advantage, be painted in different colours at inter- 

 vals equal to the differences between diameter or girth 

 classes, so that each colour corresponds to a class. It has also 

 been found a wise precaution to attach to the trees measured 

 paper labels of the same colours. 



Thus, snpposin^ there were four classes of trees, the colours mi>;ht be — 

 Class I, diameters above 2 feet, corresponding colour, white. 

 „ II, „ 1^ to 2 „ „ „ green. 



„ III, „ 1 to 1| „ „ „ red. 



,, „ blue. 



., IV. 



i to 1 



Where trees of different species are separately recorded 

 the shapes as well as the colour of the labels may vary. 

 Thus species A may be marked with square tickets, species 

 B with triangular tickets, species C with round tickets ; and 

 so on. 



Each enumeratirg party consists of one recorder and of as msiiiy gangemen and 

 coolies as are necessary. The recorder is provided with a pencil and with a blank 

 book ruled in columns for the required number of diameter classes. The columns 

 may be sub-divided so as to show separately sound and unsound trees and kinds 

 of trees to be separately recorded. The vertical columns are headed by the names 

 of the colours on the beam of the gauge which correspond to the diameter 

 classes, and each gaugeman is provided with a bag, coutaining io separate pockets 

 the tickets of different kinds and shapes, and with a gauge or calipers. The gauge- 

 men advance in line and measure each tree at breast-height from the ground. After 

 a tree is measured the gaugeman calls out its native name, the colour denoting its 

 diameter class, and, in the case of the highest classes, whether it is sound or unsound. 

 The recorder then makes the necessary entry in his book, noting each group of ten 

 trees separately. This record can suitably be made by two vertical rows of four dots, 

 each row crossed diagonally by lines from corner to corner, as in the example on 

 page 60. 



