MISCELLANY. 
159 
silica separated by filtration, and the filtrate precipitated with carbo- 
nate of ammonia- the precipitate, when well washed and heated to 
redness, weighed 0.135 grm.^ and consisted of alumina; hence the 
ash contains 38.5 per cent, of alumina. It acquired a beautiful blue 
colour when treated before the blowpipe with a solution of nitrate of 
cobalt. 
This ash contained, moreover, 16 per cent, of silica soluble in 
potash, and only 6 per cent, of lime. The other constituents were 
magnesia, potash, soda, manganese, iron, phosphoric acid and sulphuric 
acid, which were not accurately determined. The aqueous solution 
was not alkaline in reaction. This lycopodium grew upon a yellow, 
aluminous, sandy heath, which contained only a trace of humus. 
0.35 grm. of the ash oi Juniperus communis^ which was growing close 
to the lycopodium, was tested for silica. The ash was prepared from 
the summits of the shoots, which were thickly covered with needles. 
Alumina was decidedly present, but the quantity did not amount to a 
millegramme. It contained only 2.5 per cent, of silica, but 28.5 per 
cent, of lime. 
Moreover, in 0.5 grm. of the ash of Erica vulgaris^ which also grew 
close to the Lycopodium compJanatum, a small but appreciable quantity 
of alumina was present with 17 per cent, of silica soluble in solution 
of potash. The delicate summits of the shoots covered with leaves 
were the only parts used for this examination. 
Alumina was also found in the leaves of Hellehorus niger, which had 
grown in a garden soil abounding in humus. 
The leaves of the Pinus sylvestris contained no trace of the alumina. 
The tree grew upon a rich sandy soil. 
Hence there is no doubt that certain plants contain alumina. 
The remarkable circumstance, that the ash of Lycopodium compla- 
natum contains more than 38 per cent, of alumina, Juniperus communis^ 
growing close to it, a mere trace, whilst many plants, according to 
recent analyses, contain none, appears to justify the conclusion that 
the roots of plants containing alumina either exert a peculiar catalytic 
power upon the aluminous compounds with which they are in contact, 
or excrete an acid ; for were the aluminous constituents of the soil 
soluble per se in the fluids of the soil, they would also be absorbed by 
other plants. 
This consideration induced the author to test the reaction of the 
roots of Lycopodium and Juniperus ; and he found that the perfectly 
fresh uninjured smaller roots of Lycopodium complamdum, free from the 
soil, when placed upon moistened litmus-papei, had an acid reaction, 
whilst the root of Juniperus communis did not exeit this action. — Chem. 
Gaz.j from the Journ. fur prakt. Chem. 
