356 
LYCOPODIACEiE. 
it with powdered birch-leaves. The plaun-powder has the pro- 
perty of igniting only when it is dusted through a flame in the 
air, and not otherwise, even if a torch or light be placed in it, 
or it be cast on live coals. In case the plaun is not to be ob- 
tained, finely powdered sweet-scented gum or rosin will answer 
the purpose, and this, besides the amusement, produces a plea- 
sant smell. The plaun has no particular smell and produces no 
smoke.”^ Subsequent writers appear to have curtailed and 
garbled these interesting remarks, rather than verified them by 
their own observations. 
In some of the chemists’ shops of this country the seed of 
Lycopodium is kept as an article of sale; and Mr. Luxford, who 
has tried the experiment, bears ample testimony to its inflam- 
mable property. The demand for this article, as may be sup- 
posed, is extremely limited, yet a friend has informed me that 
he is acquainted with a chemist who has received an order for 
several pounds weight of it ; the purpose for which this large 
quantity was required is unknown. Sir J. E. Smith says that 
the seeds are still sold in the shops in Germany for the purpose 
of producing artificial lightning on the stage :f this use must 
however be very limited, on account of the difliculty of procu- 
ring the seed in any quantity ; and moreover, as mentioned 
above by Olearius, pulverised rosin is found to be a cheap and 
efficient substitute. I have lately been informed that these seeds, 
spread upon a plate of metal, have been employed in Chladni’s 
lectures to illustrate the vibration produced by sound. 
Many writers have said a good deal of the power of the pow- 
der or seed to repel water : it is certain that this property is ob- 
servable after a fashion, if we scatter a quantity of the powder 
on a basin of water ; when the surface is covered the finger may 
be partially immersed without becoming wet. This property 
has induced the manufacture of what has been called “ the pa- 
tent Lycopodium waterproof cloth,” an advertisement of which 
must lately have attracted the notice of many botanists. I do 
not, however, presume to say that the fabric in question is im- 
proved by the use of Lycopodium seed, or even that Lycopodium 
* Olearius, Itin. Muscovit. Persic, lib. iv. cap. 24. f Eng. Flor. iv. 318. 
