DAIRY MEETING. 1 23 



analysis of the hay, but supposing it to have the same analysis 

 as corn, you will see that it is not nearly as available to the 

 animal, because it is not as digestible. 



Now I will go through the same process with cottonseed 

 meal. We will take a high grade, which we will assume to 

 contain 45 per cent of protein. In the high grade cottonseed, 

 83 per cent of the protein is digestible, 96 per cent of the car- 

 bohydrates, and 100 per cent of the fat. In a low grade cot- 

 tonseed meal only 72 per cent of the protein is available, 68 per 

 cent of the carbohydrates and 90 per cent of the fat. Another 

 illustration of "To him that hath shall be given." That which 

 is good is good in two ways, not merely from its chemical com- 

 position but also from its availability. 



COMMERCIAIv VALUE OE PROTEIN AND CARBOHYDRATES. 



I have passed very quickly over those elementary lessons in 

 chemical composition and digestibility, which you all know. 

 We have talked about fertilizers and their cost, and we can talk 

 in a fairly intelligent manner of the cost of a pound of potash, 

 phosphoric acid or nitrogen in our fertilizers. Today I 

 would like to talk about the cost of the nutrients in different 

 feeding stuffs. While I have tried to get the average market 

 prices from both the retail and the wholesale dealers, by ton lots 

 and by carload lots, what I am more interested in than the price 

 per ton is the price per pound of protein, nitrogen-free extract 

 and fat. And because I want you to follow me and be able to 

 work these problems out after you get home, I did not prepare 

 charts, but will make them as we go on. Now what we want 

 in the first place is something that we can take for a unit. 

 Every spring the directors of the New England experiment 

 stations get together somewhere, usually at New Haven, some- 

 times in New York and sometimes in Boston, and by carefully 

 comparing the data which they have collated relative to the retail 

 prices of the materials which go to make up commercial ferti- 

 lizers — nitrate of soda, tankage, acid phosphate, etc., they derive 

 what they call the trade values for phosphoric acid, potash and 

 nitrogen, as they have sold in the markets in different forms 

 during the preceding three months. I wish to find in the same 

 way, if possible, some standards that we can use as a basis for 

 our work. 



