74 
DOUBLE FLOWEES. 
material is, in fact, operated upon by this system, in a manner exactly corresponding to 
the processes by which the explosive action of gunpowder is regulated to so remarkable 
an extent. Some results, which are admitted by the most sceptical as encouraging, have 
already been arrived at, in the systematic course of experiments which are in progress, 
with the object of applying the methods of regulation, pointed out, to the reduction of 
gun-cotton to a safe form for artillery purposes. Its arrangement in a form suitable for 
small arms is a much less difficult problem, which may be considered as approaching a 
perfect solution. For employment in shells and for military mines, both land and sub¬ 
marine, the compressed or solid form of gun-cotton presents special advantages, on 
account of the great compactness which may be imparted to it; a given weight arranged 
so as to ignite instantaneously under pressure (i. e. in strong vessels), may be made to 
occupy the same space as an equal weight of gunpowder, whereas the forms of gun¬ 
cotton hitherto applied to these purposes occupy about three times the space of gun¬ 
powder. 
Beautiful pyrotechnic effects may be readily produced by means of gun-cotton, 
though the absence of smoke, which, in some of its applications (especially in mines), 
would constitute an important advantage, detracts from some of the effects which may 
be obtained with pyrotechnic compositions. On the other hand, gun-cotton fireworks 
may be displayed in-doors without inconvenience. 
There appears at present no reason to doubt that the application of gun-cotton with 
great advantage to at least some of the more important purposes for which gunpowder 
is used, will, ere long, be fully established, and that this interesting explosive agent is 
destined to occupy a permanent and prominent position among the most important 
products of chemical industry. 
DOUBLE FLOWEES. 
Is the appearance of double flowers in some plants, that is to say the partial or com¬ 
plete transformation of the sexual organs into petals, the result of high cultivation, or 
must the change in question be attributed to physico-climatical influences ? In modern 
times the opinion has been repeatedly expressed that the double state is the result of 
culture; consequently it is the effect of a rich luxurious soil, care in the supply of water, 
frequent stirring up of the earth, and the application of liquid manures and other agents 
which are supposed to produce double flowers. This, however, according to our view, 
is not the cause of doubleness. In the first place we consider it necessary to direct at¬ 
tention to the cultivation of Stocks, in order to see in what way this is accomplished to 
obtain seeds from plants, the majority of which shall produce double flowers; and then 
we will adduce some phenomena which may perhaps serve as supports of our theory. 
Stocks intended to supply seeds of the above-mentioned character are cultivated in 
pots, placed on stages, with arrangements to protect them from rain and dew. These 
plants are only furnished with just sufficient water for their preservation, causing a 
spare growth, and in consequence of this the flowers produce defective sexual organs. 
The seeds from these plants are mostly of an abnormal sha]ie, which is so striking 
that experienced cultivators are able to separate those which will furnish double flowers 
from those which^vill produce single ones. According to this, it would appear that the 
starved state of the plants brought about by Avithholding water is the cause of their 
bearing seeds which produce flowers whose capability of generation is wanting through 
the change of the sexual organs into petals. To explain the cause of this phenomenon 
more clearly, we maintain that water plays a double part in vegetation; in one of its 
constituents it furnishes an indispensable element, and then it also serves to convey the 
ingredients of the soil through the roots into the plant. 
If a soil were ever so rich, but deficient in water, plants would nof grow in it on hot 
days. In the absence of this root-function the leaves could not inhale from the air 
carbonic acid and ammonia—vegetation would be at a stand-still. Under such condi¬ 
tions we see that many cereals, barley for instance, when only a few inches high, come 
into ear. The potato produces imperfect stolons, but these, after the first soaking rain 
sets in, form tubers, which we had good opportunity of obsendng in the course of last 
