106 
PHYSIOLOGICAL VIEWS. 
The absence of light is favourable to the germination of seeds ; 
for hght acts upon plants in such a manner as to take away oxj^gen 
by the decomposition of carbonic acid gas, and to deposite carbon; 
now this is just the reverse of the process required in germination, \ 
where the carbon must be evolved and the oxygen in excess. 
A certain degree of heat is necessary to germination. Seeds 
planted in winter, will remain in a torpid state ; but as soon as the ^ 
warmth of spring is felt, the embryo emerges into life. By increas- j 
ing heat, the vegetating process of seeds may be hastened ; thus the j 
same seed, which with a moderate degree of heat would germinate ■ | 
in nine hours, may be brought to this state in six hours, by an in- 
crease of temperature. Too great heat destroys the vital principle j 
thus corn which has been roasted cannot be made to vegetate. The 
process of malting consists in submitting some kind of grain, (barley 
is most commonly used,) to a process which causes an incipient i 
state of germination ; this is done by moistening the grain, and ex- ! 
posing it to a suitable degree of w^armth ; as soon as germination \ 
commences, the process is stopped by increasing the heat. The 
taste of the grain is then found to have become sweetish. The term i 
malt is given to grain which has been submitted to this process. 
When mixed with water it forms a sweet liquor ; and the fermenta- 
tion of this liquor produces beer. 
There is a great difference in plants as to their term of germina- 
ting ; some seeds begin to vegetate before they are separated from 
the pericarp.* jj 
In the greater number of vegetables, however, there is no germin-' i] 
ation until after the opening ol" the pericarp and the fall of the seed. ' 
The time at which different species of seeds, after being committed 
to the earth, begin to vegetate, varies from one day to some years. 
The seeds of grasses, and the grain-like plants, as rye, wheat, corn, 
&c., germinate within two days. The cruciform plants, such as 
radish and mustard, the leguminous, as the pea and bean, require | 
a little more time. The peach, walnut, and peony, remain in the 
earth a year, before they vegetate. . .,. 
All kmde of plants gci unnate sooner, if they are sown niimedi- 
ately after being separated from their pericarps. Many vegetables 
preserve their vital principle for years ; some lose it as soon as they 
are detached from their pericarps. This is said to be the case with 
respect to coffee and tea. The seeds of some of the grasses, as 
wheat, &c. are said to retain their vital principle even for centuries. , 
It is asserted that mosses, kept for near two hundred years in the [ 
herbariums of botanists, have revived by being soaked in water. [ 
An American writerf says, that " seeds, if imbedded in stone or dry ; 
earth, and removed from the influence of air or moisture, might be ' 
made to retain their vegetative quality or principle of life for a 
thousand years." But he very rationally adds, "hfe is a pi-opeity 
which we do not understand ; yet life, however feeble and obscure, 
is always hfe, and between it and death, there is a distance as great 
as existence and non-existence." 
* In the month of January, on observing the seeds of a very juicy apple, which had 
been kept in a warm cellar, I saw that they were swollen, and the outward coat-^ had 
bursi; examining one seed, by removing the tegument and separatmg the cotyledons, 
I saw, by the help of a microscope, the embryo as if in a germmatmg state ; the rad- 
icle was'like a little beak ; in the upper part or plume was plainly to be seen the tuft 
of leaves and the stem. 
t E. Barton. . 
The absence of light favourable to the germination of plants— Heat— Effects of too 
great heat exemplified in the process of malting— Malt— Season of germinating— Tmiu 
of germinating varies— Vital principle of fruits. 
