26 BULLETIN 521, U. S. DEPARTMENT OF AGEICULTUEE. 



Record and report: Each student should make a record of items of 

 interest and write a report of the trip in which the following ques- 

 tions are answered: What are the requirements of good sirup? 

 What equipment is needed? Discuss the degrees of efficiency of 

 roller mills in connection with a description of the grinding process. 

 What kind of evaporator is best suited to farm use? What is tlie 

 most efficient method of straining the juice? Discuss the use of a 

 Baume hydrometer in connection with the boiling of the sirup. 

 What factors are to be considered in connection with a prevention of 

 the sirup crystallizing? Discuss the use of lime in connection with 

 removal of impurities. How is sulphur used ? What are the funda- 

 mental principles which underly the canning of sirup and other 

 food products? What factors will determine the price received for 

 the product? 



Note. — This exercise may be adapted to a study of tlie making of sorghum 

 sirup. 



Lessons 19 and 20. — Tohacco. 



Special references. — The following Farmers' Bulletins: 60. Methods of 

 Curing Tobacco ; 120, • The Principal Insects Affecting the Tobacco 

 Plant ; 343, The Cultivation of Tobacco in Kentucky and Tennessee ; 

 523, Curing Tobacco ; 571, Tobacco Culture. 



Exercise 28. — Production of Tohacco Plants, 



Purpose: To give students practice in management of a seed bed 

 and to test depths for planting. 



Directions: Each student should participate in the preparation 

 and planning of a seed bed for tobacco and care for the plants until 

 they are ready to set out in the field. The work maj^^ also include 

 the setting of the plants wherever it is possible. A portion of the 

 seed bed should be divided to test depth of planting, as follows : ( 1 ) 

 On the surface, (2) barely covering seeds with soil, and (3) one-half 

 inch deep. If it is not possible to have seed beds out of doors, 

 small flats may be used in the sunny windows of the laboratory or 

 classroom. 



Note. — This exercise should be omitted where tobacco is not an inportant 

 crop. 

 Lessons 21, 22, and 23. — Sweet Potatoes. 



Special references. — The following Farmers' Bulletins : 324, Sweet Pota- 

 toes ; 548, Storing and Marketing Sweet Potatoes. 



Exercise 29. — Propagation of Sweet Potatoes. 



Purpose: To give students practice in the production of plants 

 and to furnish material for a study of the sweet-potato plant. 



Directions: This exercise should provide practice to all students 

 in each of the following operations: (1) Selection of seed, (2) mak- 

 ing of hotbed, (3) planting and care of bed, and (4) drawing and 



