274 BOARD OF AGRICULTURE. 



in the fattening of an ox, in the support of a draught horse 

 or of a milch cow, the farmer should know, not merely that 

 water, oil, albuminoids, etc., are absolutely required, but 

 also demanded in such and such proportions. The nails and 

 pins that are put into a house, beyond what are needed for 

 binding the structure, are not only a waste of material in 

 themselves, but may become a detriment to the building. 

 So the want of due proportion among the elements of cattle 

 food may be, and unquestionably is, in fact, an immense 

 waste and damage to our agriculture. 



In the Experiment Stations great numbers of practical 

 trials have been carried out for the purpose of ascertaining 

 the best quantities and proportions of the food-elements to 

 use for the various purposes of the stock keeper, and the 

 results that are now accepted as the best ai^i^roximation to 

 truth, are given in tables of so-called "Normal Kations." 



These " Normal Rations " are confessedly approximate and 

 imperfect ; but they are based upon experiment, and they 

 have an undeniable valuie. By their help the farmer can 

 .calculate the probably best combination of any sorts of cattle 

 ;food that are at any time accessible to him. He can determine 

 what to buy and what to sell to the best advantage of his 

 cattle, his manure heap, and his cash on hand. And although 

 the experimental foundation of these tables is not yet broad 

 enough to support all the deductions that may be made from 

 them, they have been useful in practice, and are invaluable 

 as a safe basis for further inquiries. 



The builder, in making his estimates of the materials need- 

 ful to construct a house, allows, in case of lumber, a large 

 percentage for loss by defects and unavoidable waste in cut- 

 ting. He also provides for small waste of nails, while most 

 of the other hardware required is expected to " hold out." 

 The waste portions of cattle food must in like manner enter 

 into the farmer's estimates. He must know to what degree 

 the animal can build into its structure or otherwise make 

 profitable use of the elements of all varieties of feeding stuff. 



From this point of view, another class of investigations has 



