322 THE GROWTH OF PLANTS AND ANIMALS 



b) Moisten with water a piece of blue litmus paper and drop 

 it into bottle a). Note the change and make inference. 



3) Carbonate of lime manufacture: 



a) Pour a tablespoonful of lime water into the bottle of 

 2, b) and shake vigorously, keeping the bottle tightly covered. 

 Note the changes and write out observations. 



b) Pour 1 oz. of clear lime water into a clean bottle and 

 blow the breath through it by means of a piece of small tubing. 

 Or, blow breath into the bottle, cover and shake, repeating if 

 necessary until the effect is produced. 



4) Pour carefully a small amount of hydrochloric acid into 

 bottles 2) and 3), so that it. will run down their sides. Note 

 the formation of bubbles of carbon dioxide again set free 

 through the decomposition of the carbonate by the acid. 



5) Hydrogen manufacture: 



Place closely coiled strips of sheet zinc in a test tube until 

 it is half full. Cover with dilute hydrochloric acid. Close 

 with a perforated stopper containing S tube. Collect the 

 hydrogen gas in an inverted bottle on the tin shelf of the 

 pneumatic trough. Withdraw the tube while the gas is still 

 coming freely and touch a lighted match to the end of the tube. 

 Note the character and heat of the flame. Hold a piece of cold 

 glass a short distance above the flame and note the condensa- 

 tion of water. Open bottle and apply lighted match. 



II 



Materials and apparatus : V2 oz. powdered chlorate of potash ; 

 % oz. manganese dioxide; sulphur; small piece of light iron 

 wire or watch spring (broken springs from jeweller) ; small 

 bits of magnesium, copper and zinc; splinters of pine wood; 

 lime water; stick of phosphorus % to 1 in. long; matches or 

 candle; ice or cold water; samples of soil; 6 wide-mouthed 

 bottles about 8 oz. ; 6 test tubes with 1 perforated cork or 

 rubber stopper; several pieces of strong glass tubing, Vs in- 

 opening, 12 in. long, bent to S shape and fitted to stopper; 

 small deep pan with perforated tin shelf, to serve as a pneu- 

 matic trough ; tin cup ; scales capable of weighing ^4 grain or 1 

 centigram (decimal weights preferred) ; alcohol lamp or Bunsen 

 burner; sheet tin. 



