CATTLE, HOW TO BUY AND SELL. 
207 
fiie author himself, prove the soundness of our opinion. The most skill- 
ful, when called to decide on the qualities of cojvs, whose yield of milk 
was well known, erred seven times on eight cows, and fifteen times on 
twenty-one. And, lest these errors may be attributed to chance, on ac- 
count of the small number of cows submitted for trial, we should mention 
that other estimates proved erroneous 152 times on 174 cows, and 321 
times on 352, and that the error amounted to 1)21 pints of milk on, a total 
of 2,683 pints ; in other words, there was error in regard to almost all 
the cows ; and error amounting on an average, on each, to more than a 
third of the yield. On some individuals the estimates were wrong to the 
extent of from 17 1-2 to 21, and even from 26 to 28 pints a day. 
Such is the truth as to the perfect nicety claimed for the escutcheon 
system. The system cannot do more than furnish an approximate esti- 
mate of the quantity of milk, and that in regard not to all, but only to 
the majority of cows. 
What, then, has led so many persons to put confidence in M. Guenon’s 
discovery? The great talents and knowledge of the author. Tho system 
has obtained the credit due to the experience of him who applied it. 
By his discovery M. Guenon has rendered great seryice to agriculture ; 
the escutcheon has tho advantage of furnishing a mark which can be 
easily discerned, and estimated even by persons of no groat experience 
in the selection of cows — a mark perceptible on very young animals, and 
on bulls as well as heifers — a mark which, when disencumbered of the 
complicated system in which it has been wrapped up will be in common 
use and facilitate the increase of good cows, by not allowing any but 
those of good promise to be reared. 
Milkers in all Breeds. 
Professor Magne also gives the following concise directions in relation 
to choosing a good cow, where he says : 
“Wo find good milkers in all breeds, but they are rare in some and 
Very common in others. It could not be otherwise. Milk properties, 
depending on the conditions which determine the formation of breeds, 
are due partly to the climate, the soil, the air, and the plants of the 
countries where the breeds have originated ; and must therefore vary in 
our different breeds . of horned cattle, with the hygienic condition! 
peculiar to each locality. 
“Milkers, and more especially animals intended for breeding, must ba 
(so'ented among breeds celebrated for abundance of milk. Not that we 
•an hope to import into our department, with a dry and warm climate 
