340 MISCELLANEOUS. [1873. 



or with fine hair, so that when such leaves or fruit are immersed 

 in water they appear as if encased in thin glass ? It is really 

 a pretty sight to put a pod of the common pea, or a raspberry 

 into water. I find several leaves are thus protected on the 

 under surface and not on the upper. 



" How can water injure the leaves if indeed this is at all 

 the case ? " 



On this latter point he wrote to Sir Thomas Farrer : — 



" I am now become mad about drops of water injuring 

 leaves. Please ask Mr. Paine * whether he believes, from his 

 own experience, that drops of water injure leaves or fruit in his 

 conservatories. It is said that the drops act as burning-glasses ; 

 if this is true, they would not be at all injurious on cloudy 

 days. As he is so acute a man, I should very much like to 

 hear his opinion. I remember when I grew hot-house orchids 

 I was cautioned not to wet their leaves ; but I never then 

 thought on the subject. 



" I enjoyed my visit greatly with you, and I am very sure 

 that all England could not afford a kinder and pleasanter 

 host." 



Some years later he took up the subject again, and wrote to 

 Sir Joseph Hooker (May 25, 1877): — 



" I have been looking over my old notes about the " bloom " 

 on plants, and I think that the subject is well worth pursuing, 

 though I am very doubtful of any success. Are you inclined 

 to aid me on the mere chance of success, for without your aid 

 I could do hardly anything ? "] 



C. Darwin to Asa Gray. 



Down, June 4 [1877]. 



.... I am now trying to make out the use or function of 

 "bloom," or the waxy secretion on the leaves and fruit of 

 plants, but am very doubtful whether I shall succeed. Can 



* Sir Thomas Farrer's gardener. 



