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ZAUSCHNERIA CALIFOKNICA. 
all but the severest vicissitudes of our own, if it is only stationed 
where that more destructive agent, water, cannot multiply the 
power of frost by its stagnate presence, and the limited ex¬ 
perience we have yet enjoyed in the culture of the plant fully 
bears out this supposition. We have all heard, more or less, of 
acclimatizing plants, and those who have waded through the 
theories propounded for and against the idea, must have arrived 
at the conclusion that if the nature of a plant is not to be changed 
so far as to render it possible to cultivate tropical vegetation in a 
temperate region, yet its entire tissue may be altered by the 
presence of moisture, or its opposite, to so large a degree as to 
offer a very reasonable apology for those who contend that 
culture alone makes the difference. 
Plants of acknowledged tender constitutions have, in frequent 
instances, been known to withstand the severest weather under 
some peculiar circumstances ; while others generally considered 
hardy, by an opposite combination, have been annihilated. An 
inquiry into the causes of such contrary effect, it may be of the 
same degree of cold, will generally show that the disastrous 
results are traceable to the presence of excessive moisture, not 
necessarily observable in the form of water, but always in an 
immature, soft, or excited condition in the organization of the 
individual injured; to exemplify which it is only necessary to 
take a specimen of the hardiest vegetable form we possess, and 
after filling its vessels with fluid matter, or, in other words, set 
it growing, suddenly expose it to severe cold. The effect is the 
same when natives of a climate more decided in its character than 
our own are kept in an excited state by the aqueous condition of 
the atmosphere, and are thus overtaken by frost; their tissue is 
distended, ruptured, and finally broken up ; they would probably 
have withstood the cold had it been possible to withdraw the 
surcharge of fluids, but the expansion caused by frost is so great 
as to be fatal to the entire frame. An inspection of the stems 
of such things as heliotropes, fuchsias, &c., suddenly subjected 
to the action of frosts, will usually exhibit a complete rupture 
even externally, and afford a very accurate notion of how and 
with what force it acts upon forms so fragile. Frost and cold 
are commonly spoken of as being identical, but the terms are by 
no means synonymous; the most intense cold we ever experience 
