Human Foods and Their Nutritive Value

CHAPTER XI

Bread and Bread Making

502. Define leavened and unleavened bread. 503. Why is yeast used in bread making? 504. Give the characteristics of a good loaf of bread. 505. Why is flour used for bread making purposes? 506. Name the eight chemical changes that take place during bread making. 507. To what extent do losses in dry matter occur during bread making? 508. What compounds suffer losses during bread making? 509. What is yeast? 510. What chemical changes does it produce? 511. What becomes of these products during bread making? 512. How is compressed yeast made? 513. What part does the alcohol take in bread making? 514. What temperature is reached in the interior of the loaf during bread making? 515. Through what chemical changes does starch pass during bread making? 516. To what extent are soluble carbohydrates formed? 517. In what way is starch acted upon mechanically? 518. Explain the structure of the starch grains in flour and in dough after they have been acted upon by the yeast ferments. 519. To what extent are acids produced in bread making? 520. What becomes of the acids formed? 521. How may the acids thus developed affect the properties of other chemical compounds? 522. To what extent are volatile carbon compounds, other than carbon dioxid and alcohol, liberated during bread making? 523. What changes occur to the various proteids during the process of bread making? 524. Why do flours vary in quality of gluten? 525. To what extent do losses of nitrogen occur during bread making? 526. How much of the total nitrogen of flour is present as proteids? 527. How is the fat of flour affected during the process of bread making? 528. What effect does the addition of 10 per cent of wheat starch to flour have upon the size of the loaf? 529. What effect does the addition of 10 per cent of wheat gluten to flour have upon the size of the loaf? 530. What relationship exists between gluten content and capacity of a flour to absorb water? 531. Give the general composition of bread. 532. What factors influence its composition? 533. What effect does the use of skim milk and lard in bread making have upon composition? 534. How does the temperature of the flour influence the bread-making process? 535. Why is it necessary to vary the process of bread making in order to get the best results with different kinds of flour? 536. To what extent are the nutrients of bread digested? 537. How does graham bread compare in digestibility with white bread? 538. How do graham and entire wheat breads compare in nutritive value with white bread? 539. What value do graham and entire wheat breads have in the dietary? 540. Why is white bread generally preferable in the dietary of the laboring man? 541. How do graham and entire wheat flours compare in chemical composition with white flour? 542. How do they compare in mechanical composition? 543. To what is the difference in digestibility supposed to be due? 544. Are graham and entire wheat breads necessary in a ration as a source of mineral elements? 545. What is the main difference in composition between old and new bread? 546. How do different kinds of bread made from the same flour compare in composition and nutritive value? 447. How does toast differ in composition from bread? 548. What influence does toasting have upon digestibility? 549. What is gained by toasting bread? 550. How does bread compare in nutritive value with other cereal foods? 551. How does bread compare in nutritive value with animal foods?

CHAPTER XII

Baking Powders

552. What is a baking powder? 553. What are the two kinds of materials which baking powders contain? 554. Name the different types of baking powders. 555. How does baking powder differ in its action from yeast? 556. What are the cream of tartar baking powders? 557. What is the nature of the residue which they leave? 558. What are the phosphate baking powders? 559. What is the nature of the residue which they leave? 560. Why is the mineral phosphate not considered equally valuable with that naturally present in foods? 561. What are the alum baking powders? 562. What residue is left from the alum powders? 563. Which of the three classes of baking powders is considered the least objectionable? 564. Why is a new baking powder preferable to one that has been kept a long time? 565. Why should baking powders be kept in tin cans, and not in paper? 566. Why are fillers used in the manufacture of baking powders? 567. How may a baking powder be prepared at home? 568. How does such a baking powder compare in cost and efficiency with those purchased in the market?

CHAPTER XIII

Vinegars, Spices, and Condiments

569. What is vinegar? 570. How is it made? 571. Give the three chemical changes that take place in its preparation. 572. Why is air necessary in the last stage of the process? 573. What ferments take part in the production of vinegar? 574. What is malt vinegar? 575. What materials other than apples can be used in the preparation of vinegar? 576. Give the characteristics of a good vinegar. 577. In what ways are vinegars adulterated? 578. What food value has vinegar? 579. Why should vinegars not be stored in metalware? 580. What dietetic value has vinegar? 581. To what materials do the spices owe their value? 582. What is pepper? 583. What is the difference between white and black pepper? 584. What compounds give pepper its characteristics? 585. How are peppers adulterated? 586. What is mustard? 587. Give its general composition. 588. How is it adulterated? 589. What is ginger? 590. How is it prepared for the market? 591. Give its general composition. 592. What is cinnamon? 593. What is cassia? 594. What gives these their taste and flavor? 595. What are cloves? 596. How are they prepared? 597. What is mace? 598. What is nutmeg? 599. Do the spices have any food value? 600. What is their dietetic value? 601. Why is excessive use of some of the spices objectionable?

CHAPTER XIV

Tea, Coffee, Chocolate, and Cocoa

602. What is tea? Name the two plants from which it is obtained, the countries where each grows best, and the number of flushes each yields. 603. Upon what does the quality and grade of tea depend? 604. Give differences in the preparation and composition of green and black teas. 605. The characteristic flavor of tea is imparted by what compound? 606. To what compound are its peculiar physiological properties due? 607. What can you say of the protein in tea as to amount and food value? 608. Why should tea—especially green tea—be infused for a very short time, never boiled? 609. What effect has tannin upon the digestion of proteids? 610. What three points are considered in judging a tea? 611. What is the most common form of tea adulteration? 612. Describe the coffee plant and fruit, and its method of preparation for market. 613. What is the difference in the chemical composition of tea and coffee? 614. Name the characteristic alkaloid of coffee. How does it compare with theme? 615. Why may coffee not be considered a food? 616. Tell different ways in which coffee may be adulterated. 617. Which is more commonly practiced, tea or coffee adulteration? Why? 618. How may real coffee be distinguished from chicory? Why? 619. Name the three kinds of coffee in general use. Give distinguishing features of each. Which is usually considered best? 620. From what are cocoa and chocolate obtained? 621. Give the two methods of preparing cocoa. 622. What alkaloid similar to the theme and caffeine of tea and coffee is present in cocoa and chocolate? 623. What is the difference in preparation of cocoa and chocolate? 624. What are cereal coffee-substitutes? 625. What nutritive value have they? 626. How do they differ in composition from coffee? 627. To what extent does cocoa add to the nutritive value of a ration? 628. What is plain chocolate? 629. Why do chocolate preparations vary so widely in composition? 630. What treatment is given to the cocoa bean in its preparation for commerce? 631. What treatment is sometimes given to prevent separation of the cocoa fat? 632. In what ways may cocoa and chocolate preparations be adulterated?

CHAPTER XV

Digestibility of Foods

633. Define the term nutrient. 634. Do all the nutrients of food have the same degree of digestibility? 635. What is a digestion coefficient? 636. How is the digestibility of a food determined? 637. What volatile products are formed during the digestion of food? 638. Define digestible protein; digestible carbohydrates, digestible fat. 639. What is the available energy of a ration? 640. How is it determined? 641. How do the nutrients, protein, fat, and carbohydrates, compare as to available energy? 642. Why is it necessary to consider the caloric value of a ration? 643. Is the protein molecule as completely oxidized in the body as starch or fat? 644. What residue is left from the digestion of protein? 645. What part do the soluble ferments take in digestion? 646. To what extent are the nutrients of animal foods digested? 647. Which nutrient, protein or fat, is the most completely digested? 648. How do vegetable foods compare in digestibility with animal foods? 649. What effect does cellulose have upon digestibility? 650. Which of the nutrients of vegetables, protein or carbohydrates, is more completely digested? 651. What mechanical value may cellulose have in a ration? 652. Why must bulk be considered in a ration, as well as nutrient content? 653. Name the eight most important factors influencing the digestibility of foods. 654. To what extent does the combination of foods affect the digestibility of the nutrients? 655. Why does a mixed ration give better results than when only a single food is used? 656. How does the amount consumed affect the completeness of the digestive process? 657. To what extent does the method of preparing food affect digestibility? 658. What is gained, so far as digestibility is concerned, by the cooking of foods? 659. To what extent does the mechanical condition of food affect its digestibility? 660. Why is it desirable to have some coarsely granulated foods in a ration? 661. Why should the ration not be composed exclusively of finely granulated foods? 662. Why is some coarsely granulated food more essential in the dietary of the sedentary than in the dietary of the laborer? 663. How does palatability affect the digestive process? 664. Do psychological processes in any way affect digestion? 665. What physiological properties do some foods possess? 666. To what are these physiological properties due? 667. To what extent is individuality a factor in digestion? 668. To what extent does digestibility differ with individuals? 669. Why do some foods affect individuals in different ways? 670. Why is it necessary that the quantity, quality, and character of the food should vary with different individuals? 671. In what different ways is the expression "digestibility of a food" used? 672. Why is it necessary to consider the digestibility of food, as well as its composition? 673. Does the digestibility of a food necessarily indicate the economic uses that will be made of it by the body? 674. How is it possible for one food containing 10 per cent of digestible protein, and other nutrients in like amounts, to be more valuable than another food with the same per cent of digestible protein and other nutrients? 675. How is it possible for one food to contain less total protein than another food and yet be more valuable from a nutritive point of view? 676. Why is it necessary to consider the mechanical condition of a food and its combination with other foods, as well as its chemical composition? 677. What effect does lack of a good supply of air have upon the completeness of the digestion process? 678. In what ways does the digestion of food resemble the combustion of fuel? 679. What is gained by a study of the digestibility of foods? 680. Why may two foods of the same general character give different results when used for nutritive purposes?

CHAPTER XVI

Comparative Cost and Value of Foods

681. To what extent do the nutritive value and the market price of foods vary? 682. How is the value of one food expressed in terms of another food? 683. How determine the amount of nutrients that can be procured in a food for a given sum of money? 684. How compare the amounts of nutrients that can be procured in two foods for a given sum of money? 685. How is it possible to determine approximately which of two foods is cheaper, when the price and composition of the foods are known? 686. To what nutrient is preference usually given in assigning a value to a food? 687. When the difference in this nutrient between two foods is small, then the preference is given to what nutrients? 688. At ordinary prices, what are the cheapest vegetable foods? 689. What are among the cheapest animal foods? 690. Why is it not possible to determine the value of a food absolutely from its composition and digestibility? 691. Why is it necessary to consider the physical as well as the chemical composition of foods? 692. What proportion of the income of the laboring man is usually expended for food? 693. What are the most expensive foods? 694. What foods furnish the largest amount of nutrients at the least cost?

CHAPTER XVII

Dietary Studies

695. What is a dietary study? 696. How is a dietary study made? 697. What is the value of the dietary study of a family? 698. To what extent does the protein in the dietary range? 699. Why is a scant amount of protein in a ration undesirable? 700. Why is an excess of protein in the ration undesirable? 701. What are dietary standards? 702. How are such standards obtained? 703. Why is it desirable in a ration to secure the protein and other nutrients from a variety rather than from a few foods? 704. Why is it necessary to consider the caloric value of a ration? 705. How is this determined? 706. What is a wide nutritive ratio? 707. What is a narrow nutritive ratio? 708. Why should the amount of nutrients consumed vary with the work performed? 709. How should the nutrients be apportioned among the meals? 710. What are some of the most common dietary errors? 711. What analogy exists between human and animal feeding? 712. What is gained by the rational feeding of both humans and animals? 713. What use can be made of the results of dietary studies for improvement of the dietary? 714. Why is it not possible for animal foods to compete in economy with cereal and vegetable foods? 715. Is a well-balanced ration and one containing an ample supply of nutrients necessarily an expensive ration? 716. Show how it is possible for one family to spend less money for food than another family, and yet secure more digestible nutrients and energy. 717. What are some of the most erroneous ideas as to food values? 718. Why is it necessary to consider previously acquired food habits in the selection of foods? 719. In general, what portion of the nutrients of a ration should be derived from vegetable foods, and what portion from meats? 720. To what extent may a ration vary from the dietary standards? 721. Why are some inexpensive foods often expensive when prepared for the table? 722. What are some of the ways in which the cost of a ration can be decreased without sacrificing nutritive value? 723. Why do different nationalities acquire distinct food habits? 724. Why is it not possible to make sudden and radical changes in the dietary? 725. Why is it not possible for a dietary which gives ample satisfaction for one class of people to be applied to another class with equal satisfaction? 726. What relationship exists between the dietary of a nation and its physical development? 727. What relationship exists between dietary habits and mental development and vigor? 728. Why is it unnecessary and undesirable to regulate absolutely the amount of nutrients consumed in the daily ration? 729. What is the general tendency as to quantity of food and amount of nutrients consumed? 730. Why do people of sedentary habits require a different dietary from those pursuing active, out-of-door occupations?

CHAPTER XVIII

Rational Feeding of Man

731. What is the object of the rational feeding of man? 732. On what is it based? 733. How does it compare with the rational feeding of animals? 734. What is a standard ration? 735. How is it determined? 736. To what extent may the nutrients of a ration vary from the standard? 737. How do you combine foods to form a balanced ration? 738. What foods are valuable for supplying protein? 739. What foods supply fats? 740. What foods are rich in carbohydrates? 741. What other requisites should a ration have in addition to supplying the necessary nutrients? 742. Why is it necessary to consider the calorie value of a ration? 743. If a ration contained an excess of carbohydrates and a scant amount of protein, how could it be improved? 744. How do you calculate the nutrients in a fraction of a pound of food? 745. Give the amounts of the common food materials, as potatoes, bread, butter, milk, and cheese, ordinarily combined to form a ration. 746. To what extent may foods differ in composition from the average analysis given? 747. What foods are subject to the greatest and what foods to the least variation?

CHAPTER XIX

Water

748. Why is water regarded as a food? 749. Does it enter chemically into the composition of plants? Of animals? 750. In addition to serving as a food, why is water necessary for life processes? 751. In what ways may water be improved? 752. What are the most common forms of impurities? 753. What are the mineral impurities of water? 754. What is their source? 755. What effect do some of these minerals have upon the value of the water? 756. What causes some waters to dissolve limestone? 757. What are permanently hard waters? 758. To what is temporary hardness in water due? 759. What is the best way to remove mineral matter from water? 760. What are the organic impurities of water? 761. What are the sources of the organic impurities? 762. What change does the organic matter of water undergo? 763. What becomes of the nitrogen of the organic matter? 764. What does the presence of nitrates in water indicate? Nitrites? 765. What is the total solid matter of a water, and how is it obtained? 766. Define the terms free ammonia; albuminoid ammonia. 767. What does the presence of chlorine in a surface well water indicate? 768. Explain natural purification of water. 769. Can natural purification always be relied upon? 770. Why does the character of the drinking water affect health? 771. What diseases are mainly caused by impure drinking water? 772. With what materials in water are the disease-producing organisms associated? 773. Why should a water of questionable purity be boiled? 774. State how the boiling should be done, to be effective. 775. Why should boiled water receive further care in its storage? 776. What effect does improvement of the water supply of a city have upon the death rate? 777. How may connections between cesspools and surface well waters be traced? 778. What impurities do rain waters contain? 779. Explain the workings of the Pasteur and Berkefeld water filters. 780. Why must special attention be given to cleaning the water filter? 781. Explain the processes employed for the removal of mechanical impurities of water by sedimentation and the use of chemicals. 782. Why should such purification be under the supervision of a chemist or bacteriologist? 783. What effect does freezing have upon the purity of water? 784. Why are precautions necessary in the use of ice for refrigeration? 785. What are mineral waters? 786. How are artificial mineral waters prepared? 787. What are the more common materials used in their preparation? 788. Why should mineral waters be extensively used only by the advice of a physician? 789. What are some of the materials used for softening water? 790. Which are the least objectionable of these materials? 791. Which are the most objectionable? 792. What can you say of the use of ammonia and ammonium carbonate for softening waters? 793. In washing clothing after contagious diseases, what materials may be used for disinfecting? 794. Why, in softening waters for household purposes, must caustic soda, potash, and bleaching powder be used with caution? 795. Why is it necessary to determine by trial the material most suitable for softening water? 796. What advantage, from a pecuniary point of view, results from the improvement of the water supply of a community?

CHAPTER XX

Food in its Relation to Household Sanitation and Storage

797. What are the compounds usually determined in a food analysis? 798. Does such an analysis necessarily indicate the presence of injurious compounds? 799. What are the sources of the injurious organic compounds in foods? 800. Why is it necessary to consider sanitary condition as well as chemical composition? 801. What are the sources of contamination of foods? 802. What is the object of the sanitary inspection of food? 803. How may flies carry germ diseases? 804. Why should food be protected from impure air and dust particles? 805. Why should places where vegetables are stored be well ventilated? 806. How may the dirt adhering to vegetables be the carrier of germ diseases? 807. Why should the cellar in which food is stored be in a sanitary condition? 808. What effect does the cleaning of streets and improvement of the sanitation of cities have upon the death rate? 809. Name the three natural disinfectants, and explain the action of each. 810. Why must dishes and utensils in which foods are placed be thoroughly cleaned? 811. Explain the principle of refrigeration. 812. What kind of ferment action may take place at a low temperature? 813. Why is some ventilation necessary in refrigeration? 814. What effect does refrigeration have upon the composition of food? 815. What relationship exists between unsanitary condition of soils about dwellings and contamination of the food? 816. Why should special attention be given to the sanitary disposal of kitchen refuse? 817. Name the ways in which this can be accomplished. 818. How may foods become contaminated through imperfect plumbing? 819. Mention the conditions necessary in order to keep foods sanitary.

REFERENCES

14. U. S. Department of Agriculture, Bureau of Animal Industry Bulletin No. 49: Cold Curing of Cheese.

15. Wiley: Foods and Their Adulteration.

16. Minnesota Experiment Station Bulletin No. 63: Miscellaneous Analyses.

17. U. S. Department of Agriculture, Bureau of Chemistry Bulletin No. 13, Part 8: Canned Vegetables.

18. Leach: Food Inspection and Analysis.

19. U. S. Department of Agriculture, Farmers' Bulletin No. 256: Preparation of Vegetables for the Table.

20. U. S. Department of Agriculture Year Book, 1905: Fruit and its Uses as Food.

21. Handbook of Experiment Station Work, 1893.

22. U. S. Department of Agriculture, Division of Chemistry Bulletin No. 94: Studies on Apples.

23. U. S. Department of Agriculture, Bureau of Chemistry Bulletin No. 69: Fruits and Fruit Products.

24. U. S. Department of Agriculture, Farmers' Bulletin No. 203: Canned Fruits, Preserves, and Jellies.

25. U. S. Department of Agriculture, Bureau of Chemistry Bulletin No. 27: Sugar Beet Industry.

26. Sadtler: A Handbook of Industrial Organic Chemistry.

27. Minnesota Experiment Station Bulletin No. 86: The Food Value of Sugar. The Digestive Action of Milk.

28. Hutchison: Food and Principles of Dietetics.

29. U. S. Department of Agriculture, Farmers' Bulletin No 93: Sugar as Food.

30. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 252: Maple Sugar and Sirup.

31. U. S. Department of Agriculture, Bureau of Chemistry Bulletin No. 13, Part 6: Sugar, Molasses, Sirup, and Confections.

32. U. S. Department of Agriculture, Farmers' Bulletin No. 121: Peas and Beans as Food.

33. U. S. Department of Agriculture, Farmers' Bulletin No. 122: Nuts as Food.

34. Maine Experiment Station Bulletin No. 54: Nuts as Food.

35. California Experiment Station Bulletins Nos. 107 and 132: Investigations among Fruitarians.

36. U. S. Department of Agriculture, Farmers' Bulletin No. 74: Milk as Food.

37. U. S. Department of Agriculture, Farmers' Bulletin No. 63: Care of Milk on the Farm.

38. U. S. Department of Agriculture, Farmers' Bulletin No. 149: Digestibility of Milk.

39. Russell: Dairy Bacteriology.

40. U. S. Department of Agriculture, Bureau of Chemistry Bulletin No. 13. Part 1: Dairy Products.

41. U. S. Department of Agriculture, Farmers' Bulletin No. 131: Household Tests for Detection of Oleomargarine and Renovated Butter.

42. U. S. Department of Agriculture, Bureau of Animal Industry Bulletin No 61: Relation of Bacteria to Flavor of Cheddar Cheese.

43. Minnesota Experiment Station Bulletin No. 92: The Digestibility and Nutritive Value of Cottage Cheese, etc.

44. Lawes and Gilbert: Experiments with Animals.

45. U. S. Department of Agriculture, Farmers' Bulletin No. 34: Meats, Composition and Cooking.

46. U. S. Department of Agriculture, Bureau of Chemistry Bulletin No. 13, Part 7: Lard and Lard Adulterants.

47. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 193: Cooking of Meats as Affecting Digestibility.

48. U.S. Department of Agriculture, Office of Experiment Stations Bulletin No. 141: Experiments on Losses in Cooking Meats. See also Office of Experiment Stations Bulletin No. 102: Losses in Cooking Meats.

49. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 66: Physiological Effect of Creatin and Creatinin.

50. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 162: The Influence of Cooking upon the Nutritive Value of Meats.

51. U. S. Department of Agriculture, Bureau of Chemistry Bulletin No. 13, Part 10: Preserved Meats.

52. Richardson, W. D., Journal of the American Chemical Society, December, 1907: The Occurrence of Nitrates in Vegetable Foods, in Cured Meats, and Elsewhere.

53. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 182: Poultry as Food.

54. U. S. Department of Agriculture, Farmers' Bulletin No. 85: Fish as Food.

55. U. S. Department of Agriculture, Farmers' Bulletin, Experiment Station Work: Digestibility of Fish and Poultry.

56. U. S. Department of Agriculture, Farmers' Bulletin No. 249: Cereal Breakfast Foods.

57. U. S. Department of Agriculture, Bureau of Chemistry Bulletin No. 50: Composition of Maize.

58. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 305: Gluten Flour and Similar Foods.

59. Hammerston: Physiological Chemistry.

60. Edgar: The Wheat Berry.

61. Minnesota Experiment Station Bulletin No. 90: Composition and Value of Grains.

62. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 101: Bread and Bread Making.

63. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 156: Digestibility and Nutritive Value of Bread and Macaroni Flour.

64. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 67: Bread and Bread Making.

65. University of Nebraska Bulletin No. 102: The Effect of Bleaching upon the Quality of Wheat Flour.

66. Snyder: Wheat Flour and Bread.

67. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 126: Bread and Bread Making.

68. Lawes and Gilbert: Experiments on Some Points in the Composition of the Wheat Grain, of the Product in the Mill and Bread.

69. U. S. Department of Agriculture, Bureau of Chemistry Bulletin No. 13, Part 5: Baking Powders.

70. U. S. Department of Agriculture, Bureau of Chemistry Bulletin No. 13, Part 2: Spices and Condiments.

71. Food Standards: U. S. Department of Agriculture. See Annual Reports of the Association of Official Agricultural Chemists.

72. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 21: Methods and Results of Investigations on the Chemistry and Economy of Foods.

73. U. S. Department of Agriculture, Bureau of Chemistry Bulletin No. 13, Part 7: Tea, Coffee, and Cocoa Preparations.

74. The Respiration Calorimeter: Year-book U. S. Department of Agriculture, 1904.

75. Year Book U. S. Department of Agriculture, 1902: Cost of Food as Related to its Nutritive Value.

76. See U. S. Department of Agriculture, Office of Experiment Stations Bulletins Nos. 82, 71, 129, 116, 37, 55, 150. See also other bulletins of the Office of Experiment Stations.

77. Chittenden: Physiological Economy in Nutrition.

78. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 98: Effect of Severe and Prolonged Muscular Work on Food Consumption.

79. Henry: Feeds and Feeding.

80. U. S. Department of Agriculture, Office of Experiment Stations: Dietary Studies in Chicago Bulletin No. 55.

81. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 116: Dietary Studies in New York City.

82. U. S. Department of Agriculture, Farmers' Bulletin No. 119: Banana Flour.

83. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 159: Digest of Japanese Investigations on the Nutrition of Man.

84. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 150: Dietary Studies at the Government Hospital for the Insane, Washington, D.C.

85. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 149: Studies on the Food of Maine Lumbermen.

86. U. S. Department of Agriculture, Office of Experiment Stations Bulletin No. 143: Studies on the Digestibility and Nutritive Value of Bread at the Maine Experiment Station.

87. U. S. Department of Agriculture, Office of Experiment Stations, Experiment Station Work, Vol. III: Wells and Pure Water.

88. U. S. Department of Agriculture, Farmers' Bulletin No. 88: Pure Water on the Farm.

89 Mineral Impurities in Water. See various bulletins of the California and New Mexico Agricultural Experiment Stations.

90. Mason: Examination of Water.

91. Department of the Interior, U. S. Geological Survey: The Quality of Surface Waters in Minnesota.

92. Fuertes: Water and Public Health.

93. U. S. Department of Agriculture, Farmers' Bulletin No. 124: Distilled Drinking Water.

94. Turneaure and Russell: Public Water Supplies.

95. Vaughan and Novy: Ptomains and Lencomains.

96. U. S. Department of Agriculture, Bureau of Entomology, Circular No. 71: House Flies.

97. Ellen H. Richards and S. Maria Elliott: The Chemistry of Cooking and Cleaning.

98. Dr. Woods Hutchinson, Saturday Evening Post, 1908: The Real Angels of the House.

99. Harrington: Practical Hygiene.

100. Price: Handbook of Sanitation.

INDEX