A square is a rectangle whose four sides are all of equal length 

 (Fig. F). 



A triangle is any figure bounded by three straight lines (Fig. 

 G, equilateral; Fig. H, right-angled). 



An angle is produced at a given point by the meeting of two 

 straight lines at that point (Fig. I, acute; Fig. J, obtuse; Fig. K, 

 right-angled). 



Adjacent angles are produced by the meeting of three straight 

 lines at a common point (as a point O in Fig. L). 



The area of a piece of land is the amount of surface it contains 

 expressed in square units. 



LINES 



A straight line has the same direction throughout. 



A curved line has no part straight. 



A broken line is composed of two or more different straight 

 lines. 



The length of a line is the number and kind of linear units it 

 contains. Thus 4 feet may be the length of a line. 



CIRCULAR MEASURE 



To find circumference of a circle, multiply diameter by 3.1416. 

 To find diameter of circle, multiply circumference by .31831. 

 To find area of a circle, multiply square of diameter by .7854. 

 To find area of a triangle, multiply base by >^ perpendicular 

 height. 



MILL FACTORS 



Mill factors means the number of board feet contained in the 

 log, less the waste. Mill factor 8, indicates 8 board feet of lumber 

 sawed, to 4 board feet wasted, in every cubic foot in the log. The 

 waste in sawing depends on the following factors: Soundness of 

 log; diameter of logs; thickness of saw; taper of logs; thickness of 

 boards sawed; skill of sawyer; quality of machinery; shrinkage in 

 drying. A good band saw mill will have a mill factor of 8, while a 

 circular or rotary, about 7. 



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