| upon their true nature. 
table tissue in its nascent and still gelatinous 
TIMBER. 
By treating the vege- 
state—as in the unimpregnated kernel of the 
almond or of the apricot, in the membranous 
matter of the cambium of the. cucumber, in the 
spongioles of radicles, and in leaves, wood, and 
other substances—with different menstrua, M. 
Payen obtained the cellular tissue in the state 
of purity, and having an elementary composi- 
tion almost identical, from whatever source 
derived; and this latter fact may be seen from 
the following table, which gives the composition 
of cellular tissue from different sources, after 
having been dried at 352° Fahr. 
Carbon. Hydrogen. Oxygen. 
Ovules of the almond tree, 43°6 6-1 50°3 
», of the apple and pear, 44-7 6-1 49-2 
, of the helianthus annuus, 44-1 6:2 49-7 
Pith of the elder, 6 43:4 6:0 50°6 
Cotton, . 44-4 6-1 49°5 
Endive, 43-4 6-1 00°5 
Banana, 43°2 6°5 50:3 
Leaves of the agave, 44:7 6:4 48:9 
Cotton of the Niveinipa) poplar 44-1 6°5 49-4 
Heart of oak, 44-5 6:0 49°5 
Pine tree, . 44-4 7:0 48°6 
Perisperm of the phiytel uphas, 44-1 6:3 49-6 
Mushroom, 44°5 67 48°38 
The primary tissue, consequently, which consti- 
tutes the skeleton of wood, is still isomeric or 
identical in elementary composition with starch. 
With mineral acids the cellular tissue further 
undergoes changes which assimilate it with starch; 
for on treating it with sulphuric acid, it is changed 
into dextrine and sugar. Woody fibre, or pure 
wood, or woody tissue, as it has hitherto been 
obtained after the action of solvents, and been 
examined by preceding chemists, differs consi- 
derably in composition from the cellular tissue, 
and consists of the following proportions of ele- 
ments :— 
Authorities. 
Hydrogen 
Oxygen 
| 
8 
2 
| S 
| é) 
Woody tissue of the oak 
418} 5-7) 52-5 V& Thenard. 
rf of the beech | 42:7} 5:8) 51:5 | Do. 
i of the box 44-41 5°6) 50:0 | Prout. 
of the willow | 44:6} 5°6| 49-8 % 
45 of the oak ADT} 6:0 | 44:3 1 ,, 
4 of the beech | 44:3} 6:0} 49-7 | Payen. 
of the aspen | 44:5] 6-1| 49-4 5 
Wood 4 in the natural state: | 45°6| 6:4 48-0 st 
» of the oak 39°4) 6.2 | 54:4 " 
» of the beech 393) 63 | 54.4 + 
» of the herminiera | 46:9! 5-3 | 47-2 ay 
From these analyses it appears that wood in the 
natural state contains more carbon than woody 
tissue obtained in the way of purification, and 
that this latter substance is also richer in car- 
| The specific gravity of every species, however, 
bon than the cellular tissue which necessarily 
forms part of it. In the purified woody tissue, 
therefore, the cellular tissue is associated with 
the principle which fills its cells, or which en- 
crusts it,—and it is to this matter that M. Payen 
{Gay Lussac} | 
453 
has applied the name of encrusting matter; it is 
wood properly so called; it is that which gives 
to timber its hardness, its tenacity; it predomi- 
nates in hard wood and in knots; it corresponds 
with the duramen of physiologists ; it constitutes 
almost the whole of the hard particles which are 
met with in woody pears and in cork, and which 
are hard enough to blunt well-tempered steel 
instruments. As this incrusting matter is fria- 
ble in many instances, it may be pulverized and 
separated from the tissue which surrounds it, 
this last tearing or yielding in shreds under the 
pestle. By means of the sieve, the incrusting 
matter may, in this simple way, be obtained 
nearly in a state of purity. The analysis of M. 
Payen shows it to consist of 53°8 per cent. of car- 
bon, 6 of hydrogen, and 40:2 of oxygen.” 
Timber greatly varies in properties and adap- 
tations, according to the comparative density, 
resinousness, and other constitutional qualities 
of the different genera and species of trees ; and 
though in every instance more dense than water, 
and capable of sinking in the form of either saw- 
dust or dried chips or thoroughly exsiccated 
billets, it, in most instances, floats in conse- 
quence of containing a large quantity of air 
within its pores. The specific gravity of the 
white woods, such as those of willow and pine, 
is about 1:46; that of the heaviest woods, such 
as those of oak and beech, is about 1:53; and 
that of a few of the most remarkable species, or 
of their most remarkable parts, is as follows :— 
Pomegranate 1°35 
Guaiac, Ebony 1°33 
Box 1°32 
Oak of 60 years old, ‘the heart eles 
Medlar , 0°94. 
Olive . 0:92 
Spanish Mulberry 0°89 
Beech 0°85 
Ash 0°84 
Hornbeam 0°80 
lew 0:80 
Apple 0-79 
Plum 0:78 
Maple 0-75 © 
Cherry 0°75 
Orange 0:70 
Quince 5 0:70 
Elm, the trunk 0°67 
Walnut 0:67 
Pear 0°66 
Spanish Cypress 0°64 
Lime , 0 - 0°60 
Hazel . é ; 0:60 
Willow ‘ : ; - 0:58 
Arbor Vite . : p 6 0°56 - 
Pine » 0°55 
Spanish white Poplar 0°52 
- Pine 0:49 
Poplar 0°38 
Cork 0:24 
is very observably affected by at once age, cli- 
mate and soil. All timber, when newly cut down, 
contains a considerable quantity of water. One 
hundred parts of walnut-tree, dried at 312° Fah- 
