126 



Mr. A. H. Church. On the Occurrence of [Apr. 26, 



of this earth. I refer, not to a vascular cryptogam, but to a member 

 of the great class of Musci. fax the water-moss, Fontinalis antipyretica, 

 alumina occurs among the ash constituents in a proportion which 

 seems too large to be quite accidental. The specimens which I 

 analysed were obtained in May from the Thames and Severn Canal, 

 near Cirencester. After having been thoroughly cleansed they were 

 analysed with the following results : — 



100 parts of ash 

 contained 



Percentage of ash f » ^ 



in dry plant. A1 2 3 . Si0 2 . 



*Fontinalis antipyretica . . 4*76 2 - 82 24*53 



Further analyses of this plant and of its near allies are needed 

 before a decisive conclusion can be drawn from this analysis. 



In a previous paper, " Notes on the Occurrence of Aluminium in 

 certain Cryptogams " (' Chemical News,' loc. cit.), I have detailed the 

 various precautions which I have taken to prevent the intrusion of 

 accidental traces of alumina during the analytical operations required 

 for its determination. How far such precautions have been taken by 

 the chemists who have recently investigated the occurrence of 

 aluminium in certain vegetable products, I am not aware. But as the 

 proportions of alumina obtained have been much smaller than those 

 recorded by the earlier analysts, it may be assumed that the determi- 

 nations are in general quite trustworthy. I now proceed to give a 

 brief notice of the more important of these later inquiries, that it 

 may be seen how their results differ from those to which attention 

 has been directed in the present paper. 



Mr. H. Yoshida found alumina in the ash of Japanese lacquer, the 

 latex of Rhus vemicifera (' Chem. Soc. Trans.,' 1883, p. 481). But 

 the quantity is quite insignificant. A tree yields annually about 

 2*5 grams of lacquer, and this contains from 3 to 8 per cent, of the 

 gum in which alone the alumina occurs. Mr. Yoshida found 51 per 

 cent, of ash in this gum, and on analysing its ash detected alumina 

 in it to the extent of 6*3 per cent, or thereabouts (' Chem. Soc. 

 Trans.,' 1887, p. 748). Now let us see to what amount of alumina 

 this corresponds per tree, assuming the maximum amount, 8 per cent., 

 of gum above-named to be present in the latex. A single tree 

 yields — 



Gum 02 gram. 



Ash in this gum 0*01 „ 



Alumina in this ash .... 0*00063 



that is, a single tree annually yields rather less than two- thirds of a 

 milligram of alumina. In other words, the latex or lacquer contains 

 0*0025 per cent, of alumina. The chief point of interest connected 



