M. Schonbein on Ozone and Osonic Actions in Mushrooms. 139 



oxygen disengaged from those oxides does not happen to be 

 I certainly cannot tell, but I think that the very fact of the mixed 

 nature of the oxygen in question is, in a theoretical point of view, 

 highly important, and speaks in favour of my notions rather than 

 against them. 



Although I have already heavily taxed your patience, I am 

 afraid I cannot yet release you from further listening to my 

 philosophical talkings, for I have still to speak of a subject that 

 has of late deeply excited my scientific curiosity, and taken up 

 all my leisure time. But to give you an idea of what I have 

 been doing these last two months, I must be allowed prefacing 

 a little. You know that I entertain a sort of innate dislike to 

 touch anything in the slightest way connected with organic 

 chemistry, knowing too well the difficulty of the subject and the 

 weakness of my power to grapple with it ; but in spite of this 

 well-grounded disinclination, I have of late, and, as it were, by 

 mere chance, been carried into the midst of that field, upon the 

 intricacies and depths of which I have been used all my life to 

 look with feelings of unbounded respect and even awe. The 

 picking up of a mushroon has led to that very strange aberration 

 of mine, and you will ask how such a trifiiug occurrence could do 

 that. The matter stands thus : what the botanists tell me to be 

 called "Boletus luridus," with some other sorts of mushroom, 

 have the remarkable property of turning rapidly blue when their 

 head and stem happen to be broken and exposed to the action of 

 the atmospheric air. On one of my ramblings I found a spe- 

 cimen of the said Boletus, perceived the change of colour alluded 

 to, and being struck with the curious phsenomenon, took the 

 bold resolution to ascertain, if possible, its proximate cause. I 

 carried home the part, set to work, and found more than I 

 looked for, which luckily enough happens now and then. 

 Being, by the short space allotted even to the longest letter, 

 prevented from entering into the details of the subject, I confine 

 myself to stating the principal results obtained from my mush- 

 room researches. Boletus luridus contains a colourless principle, 

 easily soluble in alcohol ; and in its relations to oxygen, bearing 

 the closest resemblance to guaiacum, as appears from the fact, 

 that all the oxidizing agents which have the power of bluing 

 the alcoholic solution of guaiacum, also enjoy the property of 

 colouring blue the alcoholic solution of our mushroom principle; 

 and all the deoxidizing substances by which the blue solution of 

 guaiacum is decolorized also discharge the colour of the blued 

 solution of the Boletus matter. From this fact and others, I 

 infer that this mushroom principle, like guaiacum, is capable of 

 combining with U, and is not affected by 0. Now the occur- 

 rence of a matter so closely related to guaiacum in a mush- 



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