Origin of Yield Mark. 5L 



ply — of milk in the bag at once ; thus doubling its size, 

 and making its distended appearance deceptive, and liable 

 to mislead. But the size of the Yield Mark cannot be in- 

 creased suddenly in this, or any other way, for deceptive 

 purposes, showing the advantage of its certainty. Much 

 of the udder is frequditly hidden, and it varies much in 

 form, so that its capacity cannot be readily estimated, 

 while the Yield Mark is always conspicuous to view, and 

 its size can be seen, which are further advantages. 



The teats should, if practicable, be tried before purchas- 

 ing a cow ; but a view of the Yield Mark saves the troub- 

 le of much handling, or inquiry as to the quantity of yield, 

 for though the yield may be larger than the mark indicates, 

 in exceptional cases, the mark from being produced by it, 

 correctly represents the maximum yield of cows generally. 

 Hence the size of the so-called milk vein — which simply 

 represents a large flow of blood — the fullness of the arte- 

 ries of the perineum, or even the fullness of the udder 

 itself, are less certain, as indications of yield, than the 

 Yield Mark, as the Yield Mark is an Index established 

 by Yield Weight, and therefore a constant and certain 

 Index of yield, according to the size of the Index mark. 



