ACTION OF CHARCOAL ON VEGETATION, 
159 
answer excellently for the Gesnera and Gloxinia, and also for the 
tropical Aroidecz with tuberous roots. The first two soon excited 
the attention of connoisseurs, by the great beauty of all their parts 
and their general appearance. They surpassed very quickly those 
cultivated in the common way, both in the thickness of their stems 
and dark colour of their leaves ; their blossoms were beautiful, 
and their vegetation lasted much longer than usual; so much so, 
that in the middle of November, when other plants of the same 
kind were dead, these were quite fresh and partly in bloom. 
Aroidece took root very rapidly, and their leaves surpassed much 
in size the leaves of those not so treated. The species which are 
reared as ornamental trees on account of the beautiful colouring 
of their leaves—I mean such as the Caladium bicolor, Pictetia, 
Poecile, &c.—were particularly remarked for the liveliness of their 
tints; and it happened here also, that the period of their vegetation 
was unusually long. 
A cactus , planted in a mixture of charcoal and earth, throve 
progressively, and attained double its size in the space of a few 
weeks. The use of the charcoal was very advantageous with seve¬ 
ral of the BromeliacecE and Silenacece, with the Citrus and Begonia 
also, and even with the Palmce. The same advantage was found 
in the case of almost all those plants for which sand is used in order 
to keep the earth porous ; when charcoal was mixed with the soil 
instead of sand the vegetation was always rendered stronger and 
more vigorous. 
At the same time that these experiments were performed with 
mixtures of charcoal with different soils, the charcoal was also used 
free from any addition, and in this case the best results were ob¬ 
tained. Cuts of plants from different genera took root in it well and 
quickly. I mention only the Euphorbia fastnosa and fulgens , which 
took root in ten days; Pandanus utilis, in three weeks; P. amarylli- 
folius, Chamcedorea elatior , in four weeks ; Piper nigrum, Bego¬ 
nia, Ficus, Cacropia, Chicocca, Buddleja, Hatrea, Phyllanthus, 
Capparis, Laurus , Stifftia, Jacquinia, Mimosa . Cactus, in from 
eight to ten days ; and several others, amounting to forty species, 
including Ilex, and many others. Leaves and pieces of leaves, and 
even dedimenti or petioles, took root and in part budded in pure 
charcoal. Amongst others we may mention the jioliola of several 
of the Cycadacece as having taken root, as also did parts of the 
leaves of the Begonia Selsairice, and Tacaranda Brasiliences; 
