CALCULATION OF DATA 



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straight line (Fig. 14-6). If it is suspected that the data fit a logarithmic 

 curve, plotting log x against y tests this idea by either producing a straight 

 line or failing to do so. This graph is easiest to construct on semilog 

 paper, a special graph paper on which the subdivisions on one axis are 

 logarithmic rather than equally spaced. Log-log paper, in which both 



Fig. 14-4. Hx+Ky-xj' = 



axes have logarithmic scales, is sometimes useful; it is almost a laboratory 

 joke, however, that log-log paper will make a straight line out of any 

 set of data. The logarithmic relationship could, of course, exist in the 

 opposite form, log y =^ x. 



Fig. 14-5, y — log X 



