THE COTTAGE GARDENER AND COUNTRY GENTLEMAN, September 20, 1859. 
369 
cut down in the Forest of Eontainbleau, a trunk of a Juniper 
(Juniperus communis), which was found to present, near its centre, 
a layer which had been affected by frost, covered over by ninety- 
one woody layers, and which dated, therefore, from the severe 
winter of 1709. 
An inscription written upon the trunk of a tree, and which 
penetrates to the alburnum, is covered over by the new woody 
layers, and may be found entire as long as that part of the truuk 
remains so. It was thus that Reisel found, in 1675, some capital 
letters in the middle of a Beech ; that Mayer, in 1688, found in 
the woody body of a Beech a kind of sculpture representing a 
gallows, and a person hanging ; that Albreehti, in 1697, found in 
the same tree the letter H, surmounted by a cross ; that Adami 
found, under nineteen layers of the alburnum, the letters 
J. C. H. M. It is thus that in certain trees in India there have 
been found inscriptions in the Portuguese language, which had 
been written there some centuries before, when the country was 
discovered by those navigators. It is thus that different spots, or 
regular stars, have been artificially formed in the middle of 
several trees. Two Memoires by Fougeroux de Bondaroy, in¬ 
serted among those of the Academie de Paris for 1777, may be 
particularly consulted upon this subject. 
When any accidental cause, as the hand of man, the teeth of 
animals, or simply a morbid change, hollows out a cavity in 
the alburnum, the orifice of which is sufficiently narrow to be 
covered over by the subsequent woody layers, the cavity is pre¬ 
served entire, as well as any object shut up in it. De Candolle 
found in the middle of a large piece of Oak, which ap¬ 
peared perfectly sound, a cavity partly filled with nuts and 
acorns, which had probably been carried there by dormice or 
squirrels before it was covered over by new ;woody layers. In 
the same manner bones, stones, &c., are found in similar cavities. 
When a nail is driven into a tree, so as to reach the alburnum, 
it remains fixed, and, by degrees, the new woody layers which 
are formed around it surround its base, so that it appears as if it 
had been driven into them ; sooner or later it is entirely covered 
over: it is thus that we find nails and other instruments, or the 
horns of stags, infixed, or completely sunk, in the wood of 
exogenous trees. It is by the same process that the base of the 
Mistletoe appears each year to sink into the tree, because the woody 
layers rise up around it.— (A. De Candolle's Organography.) 
Wood is consolidated fastest in those plants which are most 
freely exposed to the influence of light and air, and those plants 
grow in height the slowest. This teaches a lesson to the gardener 
he often may remember with advantage ; for it is often desirable 
to have specimens of the same shrub, varying in height; and he 
may often increase their stature, yet preserve them in health, by 
keeping them in a moist, shaded locality, during the early stages 
of growth ; and he may as certainly render them more dwarf, by 
exposing them to a drier, and the brightest atmosphere that they 
will healthily endure, and he can command. By the former treat¬ 
ment we have seen Heliotropes clustering round the pillars of a 
conservatory to the height of fifteen feet. 
From the extension of the woody fibre being greater and longer 
continued on one side of a stem or branch than on its opposite 
side, it frequently becomes contorted. Gardeners usually en¬ 
deavour to remedy this by making an incision on the inner side 
of the curvature, and then employing force to restore it to a rec¬ 
tilinear form, causing a gaping wound, and mostly failing to attain 
the object. If the incision be made on the outer side of the 
curve, thus dividing the woody fibres that continue to elongate 
most rapidly, the branch or stem, with but slight assistance, will 
recover its due form, and there will be no open wound. 
From the fact that there is invariably more woody matter de¬ 
posited on the side of a stem or branch which is most exposed to 
the air and light, gardeners have explained to them why those 
sides of their trained trees which are nearest the wall, ripen, as 
they term it, most slowly; and are benefited by being loosened 
from the wall so soon as they are relieved from their fruit. If 
they require any demonstration that this explanation is correct, 
they need only examine the trees in clumps and avenues ; their 
external sides will be found to enlarge much more rapidly than 
their internal or most shaded sides. 
Although the sap rises chiefly through the alburnum, yet it is 
not at all certain that the interior wood has become entirely inert. 
Indeed, the facts of its long continuing to increase in density, 
to change its colour, and to retain much both of liquid and 
gaseous matters, are evidences to the contrary. 
These gaseous substances, according to Boueherie, are in 
some cases equal in bulk to one-twentieth part of the entire 
trunk of the tree in which they exist. They, probably, move 
upwards along with the sap, and are more or less completely dis¬ 
charged into the atmosphere through the pores of the leaves. 
That these gaseous substances not only differ in quantity, but in 
kmd also with the age and species of the tree, and with the season 
of the year, may be considered as almost amounting to a proof 
that they have not been inhaled directly by the roots, but are the 
result of chemical decompositions which have taken place in the 
stem itself, as the sap mounted upwards towards the leaves. 
We have seen that the roots exercise a kind of discriminating 
power in admitting to the circulation of the plant the various 
substances which are present in the soil. The vessels of the 
stem exhibit an analogous power of admitting or rejecting the 
solutions of different substances into which they may be immersed. 
Thus Boueherie states that, when the trunks of several trees of 
the same species are cut off above the roots, and the lower ex¬ 
tremities are immediately plunged into solutions of different 
substances,'—-some of these solutions will quickly ascend into, 
and penetrate the entire substance of, the tree immersed in them, 
while others will not be admitted at all, or with extreme slowness 
only, by the vessels of the stems to which they are respectively 
presented. On the other hand, that which is rejected by one 
species of tree will be readily admitted by another. Whether 
this partial stoppage of certain substances, or total refusal to 
admit them, is a mere contractile effort on the part of the 
vessels, or is the result of a chemical change of the substance 
itself, or of the fibre or sap with which it comes into contact, by 
which change their exclusion is effected or resisted, does not as yet 
clearly appear. That it does not depend upon the lightness and 
porosity of the wood, as might be supposed, is shown by the 
observation that the Poplar is less easily penetrated in this way 
than the Beech, and the Willow than the Pear tree, the Maple, 
or the Plan c.—(Johnston's Lectures on Agricultural Chemistry .) 
Young wood contains more moisture and cellular tissue than 
old wood; in the latter the moisture and the cells being gradually 
filled with woody matter, or lignum. Chemists have endeavoured 
to analyse, separated the cellular tissue and the woody matter, 
but with no satisfactory results, inasmuch as that there is reason 
to believe that soaking the woods in caustic potash, and other 
corrosive liquids, formed the compounds which they detected 
during then’ investigations. We, therefore, give the analyses of 
the woods, without any attempt to distinguish one of their parts 
from another; nor in these analyses is there any allowance made 
for their sahne components. These, however, do not exceed two 
parts in every thousand, and the oxygen in the following table 
maybe reduced that much. The analyses were made in Liebig’s 
laboratory.— (Annul, de Dharm., xvii. 139.) 
Woods. 
Carbon. 
Hydrogen 
Oxygen. 
Oak ( Quercus robur ). 
49.432 
6.069 
44.499 
Beech, red ( Fagus sylvatica ) . 
48.184 
6.277 
45.539 
Beech, white. 
48.533 
6.301 
45.166 
Birch [Betula alia ). 
48.602 
6.375 
45.023 
Alder ( Betula alnus) . 
49.148 
6.217 
44.587 
Larch ( Pinuslarix) . 
50.106 
6.310 
43.584 
Spruce Fir ( Pinus abies) . 
49.946 
6.407 
43.647 
Silver Fir ( P.picea) . 
49.591 
6.384 
44.025 
Scotch Fir (P. sylvestris) . 
49.937 
6.250 
43.813 
Wild Plum ( Primus domestica) . 
49.311 
5.964 
44.725 
Wild Cherry [Primus cerasus) . 
48.824 
6.276 
44.900 
Crab Apple (Pyrus malus) . 
48.902 
6.267 
44.831 
Wild Pear [Pyrus communis ) . 
49.395 
6.351 
44.254 
Ebony [Diospyrus ebenum) . 
49.838 
5.352 
44.810 
Box ( Buxus semper Virens') . 
49.368 
6.521 
44.111 
Cork-barked Elm [TJXnus suberosa) 
50.186 
6.425 
43.389 
Black Poplai ( Populus nigra) . 
49.699 
6.312 
43.989 
Ash ( Fraxinus excelsior) . 
49.356 
6.075 
44.569 
Walnut [Juglans regia) . 
49.113 
6.443 
44.444 
Locust ( Robinia pseudacacia ). 
48.669 
6.272 
45.059 
Lime ( Tilia Puropcea) . 
Horse-ehestnut(AEsewfcs hippocasta- 
49.408 
6.861 
43.731 
num ) . 
49.077 
6.714 
44.209 
Crack Willow [Saliz fragilis) . 
48.839 
6.360 
44.801 
Maple ( Acer campestris) . 
49.803 
6.307 
43.890 
In the centre of the wood is situated the medulla or pith. It 
only exists in dicotyledonous plants; and in them is a soft, 
cellular, membranous substance, juicy when young, and extend¬ 
ing from the ends of the roots to the extremities of the branches. 
In the first stages of vegetation it occupies but a small space: it 
gradually dilates; and in shoots of a year old, and in young 
trees, it is of considerable diameter; as their age increases it 
gradually diminishes, and at length becomes totally or nearly 
extinct, its place being occupied by perfect wood. Its functions 
are little understood. It appeal’s to be connected with the pro. 
