Flowers and Gardens 



move it, here bright when it seems to 

 catch the golden reflections from above, 

 here darkening as we turn it into the 

 shade. We might almost compare it to 

 the darker yet luminous portion at the 

 base of an ordinary gas-flame. To make 

 out the cause of this let us break off" a 

 petal and examine it. We find the pearly 

 surface still there, and unaltered except 

 in its brilliancy being subdued. The 

 colour is, therefore, evidently due in part 

 to reflected light, as it seemed to be ; and 

 this may easily be proved by further ex- 

 periment. Let a narrow strip of black 

 paper be inserted into the corolla, so as 

 to cut off the light reflected from the sur- 

 rounding walls, but not that which comes 

 directly from the sun. The greater part 

 of the brilliancy is now seen to be lost. 

 Look again at the bottom of the corolla, 

 where the stamens arise from it. There 

 is a little ring of light around them which 

 no change of position can affect. But if 

 stamens and pistil be cut away, this light 

 will disappear at once, showing that it is 

 but a reflection, and very valuable, be- 

 cause illuminating the point which light 

 can least easily reach. 



But we have said that the change in 

 the severed petals was not in kind, but 



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