152 



Laboratory Arts 



true volume, and a table (or curve) representing the figures 

 obtained should be constructed and referenced to the burette 

 in some unmistakable manner. 



The burette readings and the actual volumes may either be 

 tabulated vertically, which will enable one to add the volumes 

 to any required total, or they may be placed so as to give total 

 error to any required point, which method would, of course, 

 necessitate the refilling of the burette to zero, after each 

 titration. 



SPECIMEN TABLE. 



Method A. The last column figures are taken as correct 

 for the 5 c.c. immediately before the reading, the burette reading 

 beyond this being added. 



Example. Burette reading 

 Previous 5 c.c. 



. 287 c.c. 



. 25-0 True vol. = 24*92 c.c. 



37 37 ,i 



Corrected reading . 28*62 



Method B. The " total error " of the previous 5 c.c. mark 

 is algebraically added to the burette reading. 



Example. Burette reading . . . 287 c.c. 

 Total error at 25 c.c. . . 0-08 

 Corrected reading . 28*62 



