CONTENTS. 7 



Department Bulletin No. 568. — The Presence op Arsenic in Hops: Page. 



Situation with respect to arsenic in hops 1 



Collection of materials for examination 2 



Analysis of materials 3 



Results of analyses 3 



Conclusions 7 



Department Bulletin No. 569. — The Sanitary Control of Tomato- 

 canning Factories: 



Introduction 1 



Conditions observed in several tomato-canning factories 3 



Washing 8 



Sorting 10 



Trimming 20 



Pulping 21 



Pulp-making systems - 21 



Promptness in handling stock 23 



Cleanliness in the factory 24 



Laboratory control 27 



Summary 28 



Department Bulletin No. 570. — The By-products of Rtce Milling: 



Introduction 1 



Description of the milling process 2 



Analysis of rice and its by-products 4 



Interpretation of results 13 



Department Bulletin No. 571. — The Pecan Leaf Case-bearer: 



Introduction % , . . . 1 



History 2 



Synonymy 3 



Distribution 3 



Food plants 4 



Character of injury 5 



Description 6 



Seasonal history and habits 8 



Natural enemies 14 



Methods of control 15 



Summary 25 



Recommendations for control 26 



Literature cited 27 



Department Bulletin No. 572. — The Recovery of Potash as a By-product 

 in the Cement Industry: i 



Introduction - 1 



Potash in raw materials and loss through volatilization in cement manu- 

 facture 3 



Percentage of volatilization of potash in cement plants 11 



Reliability of the results obtained 14 



Estimated percentage of potash in the flue dust from different plants 15 



Ratio of potash to soda in cement dust 17 



Potash-producing plants in the United States 18 



Acknowledgment 22 



Summary 22 



Department Bulletin No. 573. — The Sheep Industry on the Minidoka 



Reclamation Project: 



Importance of sheep production on Government reclamation projects 1 



Agricultural conditions on the Minidoka project 2 



History and present status of the sheep industry on the Minidoka project.. 4 



Methods of sheep management 6 



Future development of the industry 25 



Department Bulletin No. 574. — The Conversion of the Weights of 



Mechanical Separations of Corn, Wheat, and Other Grains into 



Percentages: 



Method of obtaining representative samples 1 



Directions for using the tables 3 



