618 Our Surroundings 



puscles and white corpuscles. It carries oxygen and nutrients to the 

 cells of the body and takes away wastes from them. 



Botany (bct'd-m) : The science which treats of plants. 



Brain: The mass of nerve tissue in the cavity of the skull, forming the 

 center of the nervous system. It consists of the cerebrum, or seat of 

 thought, the cerebellum, which regulates the movements of the body, 

 and the medulla, which influences respiration, circulation, and swallow- 

 ing and is the connecting link with the spinal cord. 



Breast wheel: A water wheel with pockets on the rim into which the 

 water flows at a point about level with the axis of the wheel, until the 

 added weight is sufficient to turn the wheel. 



Breathing: The process by which air is taken into the lungs arid carbon 

 dioxide is removed from them. 



Brick: A hard, rectangular block, usually made by baking a mixture of 

 clay, sand, limestone, and ashes. Much used in building. 



Broiling: Cooking by the direct heat of a fire. ^ 



Bronchi, or Bronchial tubes (bron'ki, bron'ki-al) : Two divisions of 

 the trachea which divide and subdivide, ending in the minute air sacs 

 of the lungs. 



Bruise: A surface injury; usually the result of a fall or blow. 



Burn: An injury caused by contact with fire, a hot substance, or a 

 strong chemical. 



Caffein (kaf'e-in) : A stimulating substance found in coffee. 



Caisson (ka'son) : A box-like room in which men work under water. 

 Compressed air keeps out the mud and water. 



Calorie (kal'6-ri) : A unit for measuring heat. One calorie (c) is the 

 amount of heat required to raise the temperature of one gram of water 

 1 centigrade. It is used in scientific work. The large Calorie (C),used 

 in measuring the heat value of foods and fuels, is equal to 1000 cal- 

 ories (c). 



Cambium (kam'bi-wm) : The growing layer of cells in plants. 



Camera: An apparatus for taking photographs by means of lenses. 



Cantilever bridge (kan'ti-lev-er) : A bridge consisting of self-support- 

 ing framed structures built out from opposite piers and either meeting 

 in the center or supporting a regular truss bridge between them. 



Capillaries (kapT-la-riz) : Small tubes that connect arteries with veins. 



Capillarity (kap-T-lar'i-ti) : The attractive force which causes liquids to 

 rise and fill minute tubes or spaces in porous substances, as the rise of 

 kerosene in a lamp wick. 



Carbohydrate (kar-bo-h5'drat) : A food substance composed of carbon, 

 hydrogen^and oxygen. Sugar and starch are carbohydrates. 



Carbolic acid (kar-bol'ik) : A powerful poison; used in strong solutions 

 as a germicide. 



Carbon: A non-metallic element occurring in coal, coke and other sub- 

 stances ; an essential part of all living things. 



Carbonates (kar'bon-ats) : Mineral substances composed mainly of car- 

 bon and oxygen; needed by the body to make protoplasm, bones, and 

 teeth. 



Carbon dioxide (dl-6k'sid) : A heavy, suffocating, colorless gas; a prod- 

 uct of burning. 



Carbon monoxide (mo-nok'sid) : A colorless, odorless, poisonous gas 

 formed by the incomplete combustion of gasoline and other substances 

 containing carbon. 



