Grading or Classifying 91 



from his polishing machine. The manufacturer 

 will be able, by examining the sample, to 

 ascertain the various proportions of the different 

 classes and make the separator specially suit- 

 able for treating the coffee that is, a separator 

 capable of separating the highest percentage of 

 firsts. 



Coffee used simply to be classified by its Old method 

 thickness, making three grades of these of Grading, 

 thirds, seconds, and firsts. The percentage of 

 firsts seldom exceeded 25 to 30 per cent. This 

 is the old and wrong way of classifying coffee, 

 because the beans, though they may be of the 

 same thickness, yet they may differ a good deal 

 in their width and length. The sample of firsts 

 by the old method of grading was very irregular. 



The European coffee markets demand 

 nowadays that coffees should be very uniform 

 in appearance, and in order to comply with this 

 demand coffee must be graded first of all by its 

 thickness, being the smallest dimension, then 

 by the width and afterwards by its length, 

 these two latter dimensions being more 

 apparent to the sight. 



Up to the present no single machine is able 

 to make the above three classifications, but two 

 machines can be combined to produce the 

 results demanded. 



