70 How a Tree Lives 



of water, making a solution of 16 grms. per litre. Dilute half of this 

 until you have a set of solutions of strengths 32, 16, 8, 4, 2 and 

 1 grm. per litre. Obtain some narcissi or other juicy stalked flowers 

 from the shops. Slit up the stalks of 7 flowers from below with 

 slits about 1 or 2 inches long. Put one flower stalk in each solution 

 and one more in distilled water. Leave them for a day, and describe 

 what happens in each case. 



4. Place the blade of a celandine or wild arum leaf in water. 

 Suck hard at the cut end of the stalk. What change do you notice 

 in the colour of the blade ? How do you account for it ? . 



5. What has happened to the soft and the hard stem you left in 

 a glass without water? Fill the glass with water. What do you 

 expect to happen now ? 



6. Use white flowered narcissus if obtainable in the shops. Put 

 their stalks in red ink, and leave them for a day. What happens ? 

 What do you see when the stalks are cut across ? Try black ink and 

 coloured inks as well. Try other flowers ; and try twigs freshly cut 

 from living trees. 



HOME WORK. 



Place a young twig about 9 in. long in water coloured with red 

 ink, having first removed a ring of bark % in. deep, about 2 in. from 

 its lower end. Leave the twig in water until the next evening. 

 Then take it out of the water. Sketch it life size. Now, beginning 

 at the upper end cut off ^ in. at a time to find out how far up the 

 red ink has reached. When you come to the red ink notice what 

 part of the stem it passes up. Has the removal of the ring of bark 

 stopped it ? Sketch the piece you have left by the side of the whole 

 twig. 



LESSON 2 



Season. Second week in February, but revise ex- 

 periment 5 in June. 



Materials required. (a) For Demonstration. 

 Chemical lecture room and laboratory useful but not 

 essential. Small saucer or crucible. Basin con- 

 taining water coloured with red ink. Glass jar 



