8 CONTENTS. 



FAOB 



Report of the chemist — Con. 



6. Resume of work of the feed and dairy section, ... 59 



(a) The feed law, 60 



(1) Low-grade by-jDroducts should be sold under their 



true names, 61 



(2) Protein v. carbohydrates, 61 



(3) Weight of feed stuffs, 62 



(4) Uniform feed law, 62 



{b) The dairy law, 63 



(1) Examination of candidates, 63 



(2) Testing glassware, 64 



(3) Inspection of Babcock machines, ... 64 



Creameries, 65 



]\Iilk depots, 66 



(c) Milk, cream and feeds sent for free examination, . 66 



{d) Analysis of drinking water, 67 



(e) Miscellaneous, 67 



(/) Testing of pure-bred cows, 68 



Report of the botanists, 69 



Diseases more or less common to crops during the year, . . 69 



Shade-tree troubles, 



Report of the entomologists, /^ 73 



Thomas slag. A short historical review, 



Composition of the slag, 77 



Manurial value of slag recognized, 78 



Methods for determining availability and adulteration, . . 78 



Chemical combination of phosphoric acid in slag, ... 80 



The use of phosphatic slag, 80 



Quantity of slag per acre, 81 



Effect of Porto Rico molasses on digestibility of hay and of hay and 



concentrates, 82 



I. Introduction, .82 



II. Experiments at the Massachusetts Experiment Station, . 84 



General summary, 102 



General conclusions, 105 



Observations at the Station, 108 



Data of the experiments, 110 



Stability of butter fat samples, 132 



Physical changes, 133 



Chemical changes, 134 



Action of heat, 138 



Additional notes for methods in fat analysis, 139 



Volumetric determination of copper, 140 



Reading tlie Babcock test, 142 



Introduction, 142 



Observations at this station, 143 



Conclusions 145 



