8 
THE COTTAGE GARDENER AND COUNTRY GENTLEMAN, October 4, 1859. 
Plants, however, like animals, can bear a higher temperature 
in dry air than they can in air charged with vapour; animals 
are scalded in the latter, if the temperature is very elevated; 
and plants die under similar circumstances as if boiled. Messrs. 
Edwards and Collins found Kidney Deans sustained no injury 
when the air was dry at a temperature of 167°; but they died in a 
few minutes if the air were moist. Other plants, under similar 
circumstances, would perish, probably, at a much lower tempera¬ 
ture. Yet others are still more enduring of great heat. On 
the banks of a thermal river in the islaud of Luqon, the 
largest of the Philippines, Sonnerat found plants of Vitex Agnus- 
Castus, together with a species of Aspalathus, or African Droom, 
growing, and as we may suppose thriving, though the roots were 
swept by the water at a temperature of 174° [ Voyage a la Nouv. 
Guinea] ; and in the thermal springs of Italy, though heated to 
the boiling point, certain species of Confervas are said to grow 
abundantly. The same is the case with many fishes. In the 
above island of Luqon, Sonnerat saw fishes frolicking in a hot 
spring, the temperature of which was found to be 150°; and in 
the province of Quito, in South America, Humboldt saw fishes 
thrown up from the bottom of a volcano, together with water 
and heated vapour that raised the thermometer to 210°. This 
was quite high enough to have killed and boiled European fishes ; 
but the fishes in question were still alive. 
Seeds, as we have before stated, are still more capable of bearing 
great heats, and we may further illustrate this by the following 
statement of Professor Henslow :— 
“ Sir John Herschel sent some seeds of an Acacia from the 
Cape of Good Hope, to Captain Smith, of Bedford, with direc¬ 
tions that they should be scalded, in order to secure their germi¬ 
nation. Captain Smith having presented the Professor with a 
dozen of these, he subjected them to the following experiments :— 
Two were placed in boiling water, and left to soak for an 
hom’, until the water had become cool; two were kept at the 
boiling temperature for one minute and a half; two for three 
minutes; two for six minutes; and one for fifteen minutes. 
Some of these were sown immediately, under a hand-glass, in 
the open border; and the rest were kept for three or four days, 
and then sown in a hotbed. The following are the results 
obtained 
Under the hand-glass,— 
One, boiled for 1 \ minute, failed. 
One „ 3 minutes came up in 14 days. 
O 210 !> 6 i) ,, ,,13 ,, 
One, not steeped at all, did not germinate. 
minute, came up in 
minutes ,, „ 
8 days. 
7 „ 
7 „ 
13 „ 
9 „ 
21 „ 
In the hotbed,— 
One, boiled for 1J 
Oue „ 3 
One „ G „ 
One _ „ 15 „ „ 
Two, in boiling water, left to cool 
Two not steeped. 
“ We cannot draw any decided inference from the single seed 
which was boiled for fifteen minutes having been more retarded 
than the rest, as it might have been a bad specimen; but it 
seems very clear, that the heat to which these seeds were exposed 
must have acted as a decided stimulus to their germination ; 
whilst it is a very singular fact that they should not have been 
completely destroyed by it.” 
Tu P ursuanc0 of this subject, at the Bristol Meeting of the 
British Association, Mr. Hope mentioned a practice, common in 
some parts of Spain, of baking corn to a certain extent, by ex¬ 
posing it to a temperature of io0°, or upwards, for the purpose 
of destroying an insect by which it was liable to be attacked. 
Dr. Richardson mentioned that the seeds sold in China for the 
European market were previously boiled, for the purpose of 
destroying their vitality, as the jealousy of that people made 
them anxious to prevent their exportation in a state fitted for 
germination. Upon sowing these seeds, lie had, nevertheless, 
observed some few of them were still capable "of vegetating.— 
(Edin. New. Mil. Journ., vol. xxi., October, 185G, p. 333.) 
Taough growing plants can bear an elevated temperature 
without injury, a very different effect is produced upon them 
by even a lower heat, after they have been separated from their 
roots. Ibis lias to be borne in mind in the drying of potherbs, 
which, though it is a process very simple, and very important 
for the winter 3 supply that it should be conducted correctly, 
is usually more neglected and more thoughtlessly practised 
than any other in the varied range of the gardener’s duties. To 
demonstrate this will only require to have pointed out how it 
ought to be managed. The flavour of almost every potherb 
arises from an essential oil which it secretes, and this being 
in the greatest abundance just previously to the opening of its 
flowers, that is the time which ought to be selected i'or gathering. 
Potherbs ought to be dried quickly ; because, if left exposed to 
winds, much of the essential oil evaporates, and mouldiness 
occurring, and long continuing, destroys it altogether, for nearly 
every plant has its peculiar mucor (mould), the food of which 
is the characteristic oily secretion of the plant on which it vege¬ 
tates. A dry brisk heat is therefore desirable. The tempei’ature 
should be 90° ; for if it exceeds this, the essential oils are apt to 
burst the integuments of the containing vessels, and to escape 
Forty-eight hours, if the heat be kept up steadily, are sufficient 
to complete the process of drying. The leaves, in which alone 
the essential oils of potherbs reside, should then be carefully 
clipped with scissors, not crushed, from the stalks, and stored 
in. tightly-corked wide-mouthed bottles. Each will thus pre¬ 
serve its peculiar aroma, not only through the winter, but for 
years, and be infinitely superior to any specimens producible in 
the forcing department, for these are unavoidably deficient in 
11a vo ur.—J. 
(To be continued.) 
THE FRUITS AND FRUIT TREES OF GREAT 
BRITAIN. 
No. XXIII. —Duchess of Orleans Peak. 
Synonyme —Beurre St. Nicholas. 
This excellent pear is one of the seedlings raised by Dr. Van 
Mons, but which it was not his privilege to see; it having fruited 
for the first time in 1847. 
The fruit is of a good size, being generally three inches and a 
half long and two inches and a half wide. It is of a pyriform or 
oblong-obovate shape, and tapers right into the stalk. 
Skin at first of a fine bright green colour, which becomes 
yellowish at maturity. It is strewed ail over with mottling and 
dots ot grey russet, and on the side next the sun it assumes a 
reddish tinge. 
