148 
WISCONSIN STATE AGRICULTURAL SOCIETY, 
Many things have been learned, and we are more nearly in pos¬ 
session of that knowledge upon which a rational system of feeding 
cattle may be based than formerly. But, as “ all is not gold that 
glitters,” so not all has proven to be true in practice that science 
has first announced as truth. It was at one time supposed that a 
comparison of the chemical composition of different varieties of food 
would enable one to tell their relative values, and tables were 
formed, giving the quantities of one food that must be substituted 
for a given quantity of another, usually taking one hundred pounds 
of meadow hay as a standard. This theory of nutritive values was 
a very plausible one, and is based upon a sure foundation of truth, 
yet in practice it has failed to prove itself the valuable aid it was at 
first expected to be. 
For this there are several reasons: 1st, two samples of hay may 
differ from each other but slightly in chemical composition, yet on 
account of the time of cutting, method of curing and storing, one 
may be much more valuable than another, because it contains a 
larger percentage of digestible material, for this must needs be 
taken into account, in any proper estimation of the value of food. 
Its nutritive value is so largely dependent upon the condition of 
the soil upon which it grew, its method of cultivation, time and 
method of harvesting, and the way in which it is served up, that 
no variety of food can be taken as a standard, and no other variety 
'Could be found of sufficiently constant nutritive value, for accurate 
•comparison, were a standard to be obtained. 
2d. Animals, like human beings, have their idiosyncracies, one 
being able to relish and digest food that is not as acceptable to 
another. 
3d. Whenever the functions of life, either animal or vegetable, 
form an element affecting the determination of value in a series of 
experiments, it is found that science cannot readily draw exact con¬ 
clusions. It points the direction in which truth lies, however, and 
it is wise to search for truth by following its guiding hand. 
Yet, experiment and practice agree in pointing to the conclusion 
that there is a close relation existing between the chemical compo¬ 
sition of food and its nutritive value, although it may not be possi¬ 
ble to express this relation by precise figures. I desire to call 
your attention to the results of some scientific experiments that may 
enable you to see how chemical composition of food and its nutri- 
