SLID I : \\lll\-: KATIOS. 



SLIDE WIRE RATIOS. 



The increasing use of the si i< U 1 wire in electrical measurements. 

 notably in connection with physical chemistry, renders the tiil>l<- <>f 

 values of 



a decided convenience. The work to which the slide wire is 'thus 

 for the most part employed demands but four-place tables. 



To use the table,~let a be the reading in millimetres on the slide wire, 

 which is supposed to be one metre long with millimetre subdivision, 

 or of any other length with division into thousandths. Find the 

 first two figures of a in the first column, and run out on this line to 

 the column headed with the third figure. The number there found 

 will give the value of the above fraction, which is the ratio of the 

 length of one section of the wire to the other. If a contains a fourth 

 figure, that is, if read to tenths of a millimetre, interpolation must be 

 made in the usual manner. 



Example. The slider reads 415.6 millimetres. 



In line 41 under 5 is found 0.7094. Interpolating by adding 0.6 of the 

 tabular difference 29, gives 



x = 0.7094 + 0.6 x 29 



= 0.7094+ .0017 =0.7111. 



