August 27, 1870.] 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
163 
However, in certain cases the animal produced ten 
times as much urea as in normal feeding, without 
there being any recognizable outward sign of increased 
internal work. 
From the view that the metamorphosis of nitroge¬ 
nous constituents of the body gives rise to the work¬ 
ing power, while the urea secreted is a measure of 
the metamorphosis, it would necessarily follow that 
the metamorphosis must be augmented by increased 
outward work and that tills must also increase the 
quantity of urea secreted within a given time. 
These considerations led Voit to institute the ex¬ 
periments by which he showed that, with a given 
diet, the quantity of urea secreted was the same 
during both rest and work. 
This investigation consequently demonstrated that 
though urea was indeed a measure of the nitrogenous 
constituents supplied in the food and of those meta¬ 
morphosed in the body, still it could not be taken 
as a measure of the work done by the body. An in¬ 
crease of the work did not appear to have any influ¬ 
ence in augmenting the quantity of urea secreted. 
However, in reflecting on these facts, one perceives 
at once that tills could not be otherwise, for if the 
metamorphosis of muscular substance were increased 
Fy work, a man would be able to use up his entire 
store of muscle, since the performance of work is 
subject to the will. But the work done by the muscles 
must have a limit; beyond a certain point exhaus¬ 
tion is produced. The cases in which animals are 
killed by excessive work requires a special explana¬ 
tion. 
Muscular force arises from a process that takes 
place in the muscles ; so much of them may be con¬ 
sumed for producing work as is available for that 
purpose, but no more. The application of the avail¬ 
able force may perhaps, for a time, accelerate those 
processes in the muscle by which it is generated; 
but the work done is not the cause of the metamor¬ 
phosis. 
There is no doubt as to the origin of muscular force, 
or that its seat is in the muscles themselves; neither 
is it doubted that it arises from some material altera¬ 
tion or metamorphosis of the muscular substance; 
but opinions still differ as to the process and as to 
the substances that undergo the change. 
According to one view the force is generated by 
transformation of the nitrogenous constituents of 
muscle, in which oxygen takes part, though without 
directly causing it. 
According to the other view, on the contrary, the 
force is generated by combustion, either of the non- 
nitrogenous constituents of the muscles themselves 
or of the non-nitrogenous constituents of the blood 
flowing through the muscles. 
The capability of muscular material to produce 
muscular work cannot be doubted. 
A carnivorous animal can be sustained in good 
health with meat alone and without any non-nitroge¬ 
nous material. In this case the internal work and 
heat must be produced by the transformation of flesh. 
No fact of equal significance can be brought for¬ 
ward to indicate the capability of fat or the so-called 
carbo-hydrates to generate the working force by 
their combustion. 
An animal cannot be sustained by feeding with 
fat and carbo-hydrates alone; a certain quantity of 
albuminates of muscular material is always neces¬ 
sary. Moreover the work done does not bear any re¬ 
lation to the non-nitrogenous materials of the food 
consumed; it cannot be increased by a larger supply 
of them; it is not lessened by reducing the supply of 
them, when the quantity requisite for generating heat 
is made up by an equivalent quantity of nitrogenous 
material. 
On the contrary the most every-day experience 
seems to show that the power of an individual to do 
work is, under otherwise normal conditions of diet, 
in a certain ratio to the quantity of muscular ma¬ 
terial consumed in his daily food, or to the quantity 
of material adapted for the production of muscle ; that 
the supply of such constituents of the food must be 
increased as the work to be done is increased, so that 
a working individual requires more of them in his 
food than one who is at rest. Moreover this is the 
case not only from one day to another or during a few 
days; but during a month or a year. 
(To be continued.) 
FRANKINCENSE, OR OLIBANTJM.* 
The following is an abstract of the paper on this sub¬ 
ject by Dr. Birdwood, which was referred to in our 
number for July 30 :— 
The burning of incense for purposes of worship is of 
very old date, it being represented in painting and 
sculpture on the monuments of Egypt and Assyria. 
The first mention of it and of the use of frankincense 
occurs in the Bible. In Exodus xxx. 34-36, we read 
that “ Stacte and onycha and galbanum, with pure 
frankincense,” were the “sweet spices” from which the 
“pure and holy perfume” or “confection” of divine 
prescription which was offered on the “ Altar of Incense,” 
was to be made “ after the art of the apothecary.” In 
other parts of the sacred writings it is often mentioned, 
Sheba being indicated as its source. 
Herodotus (born b.c. 484) mentions frankincense fre¬ 
quently and affirms that Arabia was the only country 
producing “frankincense, myrrh, cassia, cinnamon and 
ladanum,” and that the frankincense trees were guarded 
by winged serpents, “small in size, and of varied colours, 
whereof vast numbers hang about every tree . . . and 
there is nothing but the smoke of the storax which will 
drive them from the trees.” The Greeks obtained their 
storax from the Phoenicians. 
Theophrastus (b.c. 394-287) gives the fullest and most 
accurate account of frankincense of all ancient writers. 
Dr. Birdw’ood has supplied the following translation :— 
“ Concerning frankincense and myrrh and balsam, and 
whatsoever is like these, it has [already] been said that 
they are produced by incision and spontaneously. And 
we must [now] endeavour to tell what is the nature of 
the trees, and if they have anything peculiar as to their 
origin or collection, or other matters ; and, in like man¬ 
ner, concerning the other sweet-smelling trees; for al¬ 
most the whole of them grow in places towards the south 
and east. The frankincense-tree and myrrh and cassia 
and cinnamon grow in the Chersonese of the Arabians, 
about Saba and Adramyta, and Citibaena and Mali. But 
the trees of frankincense and myrrh grow, some of them 
on the mountain and others in private plantations at 
the foot of the mountain, on which account some of 
them are cultivated and others are not; and they say 
that the mountain is lofty and thickly wooded and 
covered with snow, and that rivers also flow down from 
it into the plains, and that the frankincense-tree is not 
large, being five cubits high and covered with boughs, 
and that it has a leaf like that of the pear-tree, only much 
smaller, and is of a glassy colour, very like rue, and has 
altogether a smooth bark like the laurel; but that the 
myrrh-tree is still smaller in size and more shrub-like, 
and that it has a hard trunk, and is twisted towards the 
* Transactions of the Linnean Society, vol. xxvii. pp. 111- 
148. On the Genus Boswellia, with Descriptions of Figures 
of Three New Species. By George Birdwood, M.D. Edin. 
I Communicated by Daniel Hanbury, Esq., F.R.S. & L.S. 
