3*6 



RECREATION. 



16 cents a dozen they were called fairly ex- 

 pensive, and at 25 cents a dozen and over 

 they were called very expensive. 



THE USES OF FOOD IN THE BODY. 

 Food serves a twofold purpose: It sup- 

 plies the body with material for building 

 and repairing its tissues and fluids, and 

 serves as fuel for maintaining body tem- 

 perature and for supplying the energy nec- 

 essary for muscular work. 



The body is like a machine, with food 

 for its fuel. The body differs from a ma- 

 chine, however, in that the fuel, i. e., food, 

 is used to build it as well as to supply it 

 with energy. Further, if the body is sup- 

 plied with more food than is needed, the 

 excess may be, and often is, stored as re- 

 serve material, usually in the form of fat. 

 In the furnace fuel is burned quickly, yield- 

 ing heat and certain chemical products — 

 carbon dioxide, water vapor and nitrogen. 

 In the body the combustion takes place 

 much more slowly, but in general the final 

 products are the same. The combustion 

 of nitrogen is, however, not so complete 

 as in a furnace. Due allowance is made 

 for this fact in calculations involving the 

 question of the energy which food will 

 furnish. 



Food consists of an edible portion and 

 refuse, i. e., bones of meat, shells of oys- 

 ters, bran of wheat, etc. Although foods 

 are so different in appearance, chemical 

 analysis shows that they are all made up 

 of a comparatively small number of chem- 

 ical compounds. These are water and the 

 so-called nutrients, protein or nitrogenous 

 materials, fat, carbohydrates and ash, or 

 mineral matter. Familiar examples of pro- 

 tein are lean of meat and fish, white of 

 egg, casein of milk and cheese, and gluten 

 of wheat. Fat is found in fat meats, fish, 

 lard, fat of milk (butter) and oils, such 

 as olive oil. Starches, sugars and woody 

 fiber or cellulose form the bulk of the 

 carbohydrates. 



The protein, fats and carbohydrates are 

 all organic substances; that is, they can 

 be burned with the formation of various 

 gases, chiefly carbon dioxide and water 

 leaving no solid residue. The mineral mat- 

 ters will not burn and are left behind when 

 a material is ignited. By analysis the nu- 

 trients have been found to be made up of 

 a comparatively small number of chemical 

 elements in varying combinations. These 

 are nitrogen, carbon, oxygen, hydrogen, 

 phosphorus, sulphur, calcium, magnesium, 

 sodium, potassium, silicon, chlorin, fluorin 

 and iron. Doubtless no single nutrient 

 contains all these elements. The body 

 tissues and fluids contain nitrogen; hence, 

 protein, which alone supplies nitrogen to 

 the body, is a necessary factor in food, All 



the nutrients except mineral matter con- 

 tain carbon, oxygen and hydrogen, and 

 can supply them to the body. 



Protein, fat and carbohydrates are all 

 sources of energy. The value of a food 

 for building and repairing the body is 

 shown by its chemical composition; that 

 is, by the quantity of the different nutrients 

 which it contains. Some other means is 

 necessary to show its value as a source of 

 energy. It is known that all energy may 

 be measured in terms of heat. In order 

 to have some measure for expressing the 

 amount of heat, the calorie is taken as a 

 unit. Roughly speaking, this is the amount 

 of heat required to raise the temperature 

 of one pound of water 4 F. One pound 

 of sugar or starch would, if burned and 

 all the heat utilized, raise 1,860 pounds of 

 water 4 in temperature; or it would raise 

 5 gallons of water from the freezing point 

 to the boiling point, but would not cause 

 it to boil. It has been found by experi- 

 ment that the fuel value of a pound of 

 protein as ordinarily burned in the body 

 is 1,860 calories; the fuel value of a pound 

 of carbohydrates is the same, while that 

 of a pound of fat is 2% times as great. 



The value of a food is usually judged 

 by several different standards. Thus it 

 must be digestible and palatable, furnish 

 the nutrients needed by the system in prop- 

 er amounts, and be reasonably cheap. 



FRESH AND SALT WATER FISH. 



Fish, using the term broadly, to cover 

 the fresh and salt water animals used as 

 food, is almost universally recognized in 

 one form or another as one of the impor- 

 tant food materials, and enters to a greater 

 or less extent into the diet of many 

 if not most American families. Few, how- 

 ever, have any adequate conception of the 

 great importance of the fisheries of the 

 United States and of the immense quantity 

 of nutritive material which is every year 

 taken from the salt and fresh waters of this 

 country. From recent data collected by 

 the United States Fish Commission it ap- 

 pears that more than 616,000,000 pounds 

 of fish, crustaceans, etc., are annually taken 

 from the waters of the New England 

 States, over 596,000,000 pounds from the 

 Middle Atlantic States, over 59,000,000 

 from the South Atlantic States, 84,000,000 

 from the Gulf States, 147,000,000 from the 

 Pacific States, and 64,000,000 from Alaska. 

 The products of the fisheries of the Great 

 Lakes exceed 108,000,000 pounds annually, 

 and the interior fisheries 19,000,000 pounds. 

 In the case of such products as clams, scal- 

 lops and oysters, the weight of the edible 

 portion only has been taken into account. 

 In addition, thousands of pounds of fish 



