THE FLOEAL WORLD AND GARDEN GUIDE. 311 



were the disgust of all beholders during the recent wretched weather, 

 a lot of this seduni, either plunged or planted out, would have been 

 acceptable, especially to those shut up much in the house, as many 

 ladies are, and who become weary of watching a washed-out garden. 

 Suppose the beds nearest the windows to be cleared of their occu- 

 pants by the 10th of September, and the beds then filled with Sedum 

 Fabarium, there would be a delightful change of scene, and the 

 prolongation of the beauty of the garden in spite of the worst 

 weather that could happen. Those of our readers who do not 

 possess this sedum we strongly advise to obtain it. Should it not 

 be wanted for pot-culture, plant it out in a sunny border, and leave 

 it to take care of itself, and it will form a fine bush, and be admired 

 by all who see it. S. H. 



OjS^ the action of charcoal on a^egetation. 



BY EDWABD LUCAS. 



N a division of a low hothouse in the botanical garden at Munich, a bed 

 was set apart for young tropical plants, but instead of being filled with 

 tan, as is usually the case, it was filled with the powder of charcoal (a 

 material which could be easily procured), the large pieces of charcoal 

 having been previously separated by means of a sieve. The heat was 

 conducted by means of a tube of wliite iron into a hollow space in this bed, and 

 distributed a gentle warmth, sufficieut to have caused tan to enter into a state of 

 fermentation. The plants placed in this bed of charcoal quickly vegetated, and 

 acquired a healthy appearance. Now, as always is the case in such beds, the roots 

 of many of the plants penetrated through the holes in the bottom of the pots, and 

 spread themselves out ; but these plants evidently surpassed in vigour and general 

 luxuriance plants grown in the common way, for example, in tan. 



Several of them, of which I shall only specify the beautiful Thunbergia alata, 

 and the genus Pereskia, throve quite astonishingly ; the blossoms of the former 

 ■were so rich that all who saw it affirmed they had never before seen such a speci- 

 men. It produced also a number of seeds without any artificial aid, while in most 

 cases it is necessary to apply the pollen by the hand. The Pereskia grew so 

 vigorously, that the P. aculeata produced shoots several ells in length, and the P. 

 grandifolia acquired leaves of a foot in length. These facts, as well as the quick 

 germination of the seeds which had been scattered spontaneously, and the abundant 

 appearance of young Filices, naturally attracted my attention, and I was gradually 

 led to a series of experiments, the results of which may not be uninteresting; for, 

 besides being of practical use in the cultivation of most plants, they demonstrate 

 also several facts of importance to physiology. 



The first experiment which naturally suggested itself was to mix a certain pro- 

 portion of charcoal with the earth in which difi^erent plants grew, and to increase 

 its quantity according as the advantage of the method was perceived. An addition 

 of two-thirds of charcoal, for example, to vegetable mould, appeared to answer 

 excellently forjthe Gesneria and Gloxinia, and also for the tropical Aroideoe 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 waj-, 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 anvl partly in 

 bloom. Aroidea) 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 



