34 BULLETIN 704, U. S. DEPARTMENT OF AGRICULTURE. 
to the fact that the short horizontal lines gradually drop below the original 
base line. Each vertical line which shows above the corresponding horizontal 
base line on its right should be counted as part of the record. 
FFP OP 7 
Fig. 3.—Details of Page impact machine for testing cementing yalue. 
The number of blows required to destroy the specimen is called its cementing 
value, An average of five determinations is taken, 
