614 LIC 
fpecies but the filamentous lichens. This however (adds 
Dr. Robert) does not detrnfl from the merit of lord Duo¬ 
dena!;!, who had never feen the works quoted above. 
The medical virtues-of this lichen were probably firft 
learned from the Icelanders, who employ it in its fre fit 
Rate as a laxative; but, deprived of this quality and pro¬ 
perly prepared, it is faid to be an efficacious remedy in 
confiimptions, coughs, dyfenteries, and diarrhoeas. Dr. 
Crichton informs us, (Med. Journ. vol. x.) that, during a 
residence of feven months at Vienna, he had frequent op¬ 
portunities of feeing the Lichen Iflandicus tried in phthifis 
pulmonalis at the general hofpital; and he conftffes, “ that 
it by no means anfwered the expectation he had formed 
of it.” That this lichen ftrengthens the digeftive powers, 
and proves extremely nutritious, there can be no doubt; 
but the great medicinal efficacy attributed to it at Vienna 
will not readily, fays Dr. Woodville, be credited at Lon¬ 
don. It is commonly given in the form of a decoCtion, 
an ounce and a half of the lichen being boiled in a quart 
of miik. Of this a tea-cup full is directed to be drunk 
frequently in the courfe of the day. If milk difagree 
with the ftomach, a fimple decoction of the lichen in wa¬ 
ter is to be ufed. Care Ihould be taken to boil it over a 
flow fire, and not longer than a quarter of an hour. In 
the London Pharmacopeia the decoftion is directed to be 
prepared by boiling down an ounce of the lichen in a pint 
and a half of water to a pint, and then {training it. 
Mr. Richard Reece recommends the farina of the lichen, 
inftead of the decoCtion, in thofe cafes in which it may 
be necefFary to employ that remedy. Little advantage, he 
thinks, can be obtained from its ufe, unlefs two or three 
ounces are exhibited in the courfe of twenty-four hours ; 
and as this quantity, given in the ufual way, mult foon 
produce drfguft in the patient, he prefers the employ¬ 
ment of the farina ; which, he fays, is exempt from this 
objection, and'“may be adminiltered, without difgulting 
the patient, to the extent of three, or even four, ounces a- 
day.’’ Tins preparation is free from the cortical and 
fibrous parts of the herb. It polfelTes, in perfection, both 
the medicinal and dietetic properties ; and, to form the 
Jelly, does not require that long codtion which proves de- 
Itrudtive to its bitter quality. It may be exhibited in the 
quantity of three drams for a dofe, boiled with half an 
ounce of chocolate or cocoa in a morning for breakfaft. 
The true Spanifh cocoa is found to anfwer belt; it ap¬ 
proaches nearly to the flavour of the chocolate of this 
country, and, being free from fugar, is lefs liable to dif¬ 
agree with the patient than the manufactured chocolate, 
which, from the milk, butter, and fugar, ufed in its com¬ 
position, is generally found more or lefs acid or rancid. 
This powder may likewife conveniently be made intro a 
kind of pottage, (a form much recommended by Bergius,) 
either in milk, water, or both, as may appear molt fuitable 
to the cafe of the patient, in the following manner: To a 
defert-fpoonful of the farina, add as much cold water as 
will make it into a foft pafte ; then pour on by degrees 
half a pint of boiling water, broth, or warm milk, ftirring 
it brilkly rhe whole time : after boiling for about ten mi¬ 
nutes, it will become a fmooth thin jelly. A little fugar, 
currant-jelly, liquorice, railins, cinnamon, butter, wine, 
or any aromatic, may be added, to render it palatable. 
Obf. on the Anti-phihijical Properties of L. Iflandicus, Lond. 
1804. We have given a figure of this fpecies on the an¬ 
nexed Plate, at fig. x. 
z. Lichen caninus, or afli-coloured ground liverwort: 
coriaceous, dilated, afeending, furrowed, grey; white, 
with brown veins and fibres beneath ; lobes very broad, 
with marginal fruit-bearing procefies. Targets in front, 
vertical, revolute, roundilh, red-brown with a pale border. 
The large!!:, molt common, and molt famous, of its tribe. 
It grows on heaths, dry paltures, and woods ; has a weak 
faint fmell, and a fharpiffi tafle. It was for a long time 
extolled as a medicine of lingular virtue in preventing 
and curing that dreadful diforder which is produced by 
the bite of rabid animals. T lie pulvis antilyj'us t a powder 
H E N. 
compofed of equal parts of this lichen and black pepper, 
was firft recommended as a prefervative againft the hydro- 
phobia by Mr. Dampier, brother of the celebrated circum¬ 
navigator; and, by the authority of fir Hans Sloane, it 
was publilhed in the Phil. Tranf. vol. xx. p. 49. The 
quantity of pepper having been found to render the me¬ 
dicine too hot, the powder was afterwards prepared of 
two parts of the lichen and one of pepper. This powder 
was afterwards adopted in the London Pharmacopeia in 
17 ZI , at the defire of Dr. Mead, who feems to have had 
repeated experience of its good effects, and who declares 
that he had never known it to fail, where it had been ufed, 
with the affiftance of cold-bathing, before the hydro¬ 
phobia came on. He directs the patient to be blooded to 
the extent of nine or ten ounces ; afterwards a dram and 
a half of the powder is to be taken in the morning fall¬ 
ing, in half a pint of cow’s milk warm, for four morn¬ 
ings fucceffively. After thefe four dofes are taken, the 
patient is directed to go into the cold-bath every morn¬ 
ing for a month, and then three times a week for a fort¬ 
night longer. On the character of Mead, the pulvis anti- 
lyH'us was long retained in the London Pharmacopeia 5 
but, on the revifion of that book in 1788, it was deferved- 
ly expunged. 
3. Lichen feriptus : leprous, whififli, bearing fmall, 
black, branched,letter-like, lines. Common on the fmooth 
bark of young trees. The cruft is a fine, infeparable, 
whitilh, film. The fructification conveys an idea of He¬ 
brew or Chinefe writing, in a very ftriking manner. 
4. Lichen geographicus ; leprous, yellowilh, with black 
lines refembling a map. Frequent on the -hard rocks of 
mountainous countries, and alrnoft as hard itfelf, at leaf!; 
to the touch, forming broad infeparable patches, of a vi¬ 
vid greenilh-yellow, or lemon-colour, curioully llreaked 
and dotted with black marks, compofed of the tubercles, 
which are flat, not elevated above the cruft, frequently 
confluent or crowded. 
5. Lichen fanguinarius: cruft tartareous, white, polilh- 
ed, uneven. Tubercles black, without a border; bright 
red within. Found on granite rocks; copioufly upon 
Cromford Moor, Derby/hire ; very rarely on the rugged 
barks of trees. This is extremely remarkable for the in¬ 
ternal ftains cf bright red, perceived when the tubercles, 
and even fome parts of the cruft, are broken ; which, re- 
feinbling blood, gave occafion to the name. 
6. Lichen ventofus: cruft tartareous, rugged, pale ful- 
pliur-coloured ; Ihields irregular, a little fwelling, blood- 
red, with a narrow pale border. Found on large expofed 
granite or fand-ftones, in mountainous places, forming 
patches as broad as the hand, eafily pared from tha rock 
when moift. The cruft is of an elegant pale lemon or ful-. 
phur colour, turning white the fecond year ; but in either 
cafe it is ftrikingly contrafted with the crimfon Ihields. 
7. Lichen tartareus : cruft tartareous, rugged, granu¬ 
lated, whitilh ; Ihields tawny buff-coloured, with a white 
margin. The largeft of the cruftaceous lichens ; and im¬ 
portant as an article of commerce. The diameter of the 
cruft is fix, eight, or ten, inches; and its thicknefs a quar¬ 
ter or half an inch. The Ihields are frequently half an 
inch wide, confpicuous for their full buff-colour, and 
white, fmooth, wavy, border. This fpecies is much ufed 
in dying, being feraped from the rocks when fully grown, 
which is about the fifth year of its age, and mixed with 
volatile alkali and alum. It is fold to the dyers in the 
form of a purple powder, called cudbear , a corruption of 
Cuthbert, the name of the inventor. This powder being 
boiled with woollen yarn, communicates a purple colour 
to it; but not to vegetable fubllances. The colour is far 
from permanent. 
8. Lichen perellus: is like tartareus on a fmaller fcale, 
with Ihields of the fame white colour as the craft, and is 
ufed likewise for dying purplilh colours, chiefly in the 
fouth of France, Litmus is prepared from this fpecies; 
for which purpofe it is gathered from the rocks in the 
north of England, and fent to London in calks. 
z 9. Licliea 
